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Round Tower, Glendalough

Round Tower, Glendalough

The Complete Guide to Irish Round Towers

Ireland’s most iconic structures are probably the romantic castles which dot the countryside, but some of its ancient buildings are a bit more mysterious. The Irish round towers have long intrigued scholars and history buffs, who have studied these free-standing pillars across the Emerald Isle.

In Irish, the towers are known as Cloigtheach – or bell towers, in English. However, there remains some debate about what these ancient towers were first created to do, and why the round structures only seem to exist in Ireland.

Here is what to know about Irish round towers, and how to visit them as you explore the many corners of the Republic and Northern Ireland.


The round tower at Clones would have originally stood at almost 23 metres in height, including the conical cap, which is now sadly missing.

The tower was built from sandstone and looks as though it may have been an early tower probably built around the 10 century. There were four storeys including the bell storey. There is a single window on each storey in the drum except for the bell-storey which had the usual four windows, one at each cardinal points on the compass. In Irish the round towers are known as Cloigteach literally meaning bell house. Also in St Tierney's graveyard are some interesting grave slabs and the wonderful tomb shrine of St Tighernach (Tierney).

The Picture above is a generalised artist’s impression by Philip Armstrong in a series Painting The Past and is not specific to Clones, however it does portray a lifestyle of the Monastic Settlement that was the seed for our town

There is a visible offset, approximately 20 cm high and 12 cm wide on the south west base of the tower, outside the graveyard wall near a viewing walkway. The tower is 15.4 m at the lowest point that it can be accurately measured, due to the bisecting walls. Height is just under 22.9 meters from the offset. The east-facing doorway is 1.64 meters above the present cemetery level and 2.12 m above the offset. Small lintelled windows face - in ascending order - S, N and E with the traditional four bell-storey windows at the cardinal compass points.

While this is a nice enough round tower at virtually it's full height, of more interest are the headstones in the well-maintained cemetery - many from the17th and mid 18th century. They feature rounded crosses with skulls and crossed bones and coffins, hour glasses and bells all symbols of mortality. Some feature the well carved coats of arms of early prominent citizens.

The monastery at Clones was founded by St. Tighernach who died in the mid sixth century. The Annals record the destruction of "all it's churches" in 836, but there is no mention of the round tower. Getty did an excavation in the 1840's below the debris-filled sill level of the tower. The results were inconclusive, as human bones that were found at the extreme lowest level (below the level of the external offset) could have come from either a burial ground that the tower was built upon or from graveyard debris used as infilling.
Other Items of Interest: Along with the early headstones in the churchyard is the Shrine of St. Tighernach. It is carved in the shape of a house complete with finials from a single stone. One of the gables features a figure St. Tighernach with outstretched arms. Not far from the graveyard where the round tower stands, is another churchyard containing "the Abbey". It is the ruin of a 12th century nave and chancel church and the graveyard also contains early headstones.

The Monastic Sites of Glendalough

In the latter part of the sixth century, St. Kevin crossed the mountains from Hollywood to Glendalough. Within 100 years, the area had developed from a remote hermitage into one of the most important monastic sites in Ireland. The monastery continued to flourish after St. Kevin’s death in 617 A.D.

By the end of the eighth century, the monastery employed up to 1000 laypeople to help grow crops and tend livestock. Monasteries were wealthy. In addition to stores of treasure, most monasteries maintained substantial stocks of food and were able to survive periodic famines. Such rich sites were often plundered. Glendalough’s remote location made it an easy target, and between 775 and 1095 it was plundered many times by both local tribes and Norse invaders. Usually the churches and houses were burned, but each time the monastery was rebuilt.

The eventual decline of Glendalough’s monastery was not due to invaders, but rather to a shift in political power. When Glendalough was annexed to the diocese of Dublin in 1152, its importance declined. Despite this, the place has retained a spiritual significance.

Glendalough’s Monastic Sites

Today the ruins of the ancient monastic site are scattered throughout the valley. Many are almost 1000 years old. The main sites are located in the area known as the Monastic City, beside the OPW Visitor Centre. Guided tours are available. Further afield are the ruins of other churches, extending from St. Saviour’s Church in the far east of the valley, to Temple na Skellig beside the Upper Lake.

All the monastic ruins in Glendalough are managed by the Office of Public Works (OPW) and are not under the auspices of the National Park. Queries about the monastic site should be directed to OPW. Entrance to all the historic sites is free of charge. All sites are open at all times. The Monastic City is also served by the adjacent OPW Visitor Centre which has an exhibition, an audio-visual show and also provides guided tours. An admission charge applies to the Visitor Centre and for the tours. Due to the archaeological nature of the sites, none of them are accessible to wheelchairs.

The Monastic City

The Monastic City is the name given to the main monastic site at the eastern end of the valley, close to the OPW Visitor Centre and the Glendalough Hotel. The following monuments can be seen in the Monastic City.

The Gateway

This building stands at the entrance to the Monastic City, and is perhaps one of the most important monuments as it is now unique in Ireland. The building was originally two-storeyed, probably with a timber roof. Inside on the west wall, is a cross-inscribed stone. Visitors entering the Monastic City from the road still pass through this ancient entrance, walking on some of the original stone paving.

The Round Tower

Perhaps the most noticeable monument, the Round Tower is about 30 metres high. The entrance is about 3.5 metres from the base. Originally there were six wooden floors with ladders. The roof had fallen in many years ago, but was rebuilt in 1876 using the original stone. Round towers were multi-functional. They served as landmarks for visitors, bell-towers, store-houses, and as places of refuge in times of attack.

The Cathedral

This is the largest of the churches, and was constructed in several phases. Of note, are an aumbry or wall cupboard under the southern window, and a piscina – a basin used for washing sacred vessels. Outside the Cathedral is St. Kevin’s Cross – a large early granite cross with an unpierced ring.

The Priest’s House

This is a small Romanesque building which was almost totally reconstructed using the original stones in 1779. The east end has a decorative arch. The original purpose of the building is unknown, but it may have been used to house the relics of St. Kevin. In the 18th and 19th centuries, it was used as a place to inter priests.

St. Kevin’s Kitchen

This church is most noticeable for its steep roof formed of overlapping stone, supported internally by a semi-circular vault. The belfry has a stone cap and four windows facing north, south, east and west, and is reminiscent of a round tower.

St. Kieran’s Church

Only low walls of this church remain. It was uncovered in 1875, and probably commemorates the founder of Clonmacnoise, a monastic settlement that had associations with Glendalough during the 10th century.

Other Monastic Sites near the Monastic City

St. Mary’s Church

Also called Our Lady’s Church, this is one of the earliest churches. It consists of a nave and chancel. The granite west doorway has an architrave, inclined jambs, and a massive lintel. The underside of the lintel has an inscription of an unusual X-shaped cross. The round-topped east window has two very worn carved heads on the outside. St. Mary’s Church is located in a field to the west of the Monastic City.

St. Saviour’s Church

This is the youngest of the Glendalough churches. It was built in the 12th century. The nave and chancel have many well decorated stones. The Romanesque chancel arch has three tiers of decoration. The east window is decorated with various carvings including a serpent, a lion, and two birds holding a human head between their beaks. An adjoining domestic building has a staircase that would have led to a room over the chancel. St. Saviour’s Church is located on the Green Road approximately 1 km east of the Monastic City.

Trinity Church

This is a simple nave and chancel church. A door in the west gable leads to a later annex, possibly a sacristy. There was a belfry in the style of a round tower, but it collapsed in a storm in 1818. Trinity Church is located beside the main road just east of the Visitor Centre.

Upper Lake Historical Sites

Reefert Church

The remains of Reefert Church are situated in a woodland setting, on the south-eastern shore of the Upper Lake close to the Information Office. Reefert derives its name from the Irish ‘Righ Fearta’ meaning burial place of the kings (referring to the local rulers – the O’Toole family). It dates from the eleventh century and is likely to have been built on the site of an earlier church. The church and graveyard were originally surrounded by a stone wall enclosure known in Gaelic as a ‘caiseal’. Most of the present surrounding walls however are modern. The upper parts of the church walls were re-built over 100 years ago using the original stones.

The Caher

This archaeological monument is found on the lawns beside the Upper Lake in Glendalough. It is a stone walled circular enclosure, measuring 20 meters in diameter. It’s original purpose and time of construction is a mystery. Similar structures can be found around the country but they were built on a much larger scale for use as defensive forts. The Caher in Glendalough is likely to be have been used as a station (stopping point for prayers) for those on pilgrimage across the mountains to the remains of St. Kevin’s monastery.

Various Crosses

The lawns by the Upper Lake are the location of several stone crosses. They may have been used as stations during pilgrimages to Glendalough.

Temple na Skellig

The ruins of this small church are located at the base of the cliffs on the southern shore of the Upper Lake. The site is not safely accessible to visitors, but may be viewed from the Miners’ Road, across the lake. West of the church is a raised platform with stone enclosure walls, where dwelling huts probably stood. The church was partly rebuilt in the 12th century.

St. Kevin’s Bed

St. Kevin’s Bed is a small cave in the cliff to the east of Temple ne Skellig. The entrance is about 8 metres above the lake. Please note that the site is not safely accessible, and has been the site of many serious accidents. It may be viewed from the Miner’s Road, across the lake. The cave runs back two metres into the cliff and was reputedly a retreat for St. Kevin and later for St. Laurence O’Toole.

St. Kevin’s Cell

Originally a small bee-hive hut, today only a circle of base stones remain to mark its location on a rocky spur over the Upper Lake.

Opening Times

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Contact Info

Wicklow Mountains National Park,
Kilafin, Laragh, via Bray, Co. Wicklow A98 K286

Glendalough’s Round Tower

Upon entering the Glendalough site via 360cities, I am greeted by what looks to be an ancient graveyard surrounded by stone tombstones and precise architecture complementing them. Looking around, my eyes land upon a large tower of sorts, which reminds me of medieval architecture that I once saw in books and cartoons. Upon further research, I learn that this is called the “Round Tower” however, despite its bland name, it is anything but simple–the tower, in its gorgeous stone build with open windows and a pointed top, served an important purpose in history.

The Round Tower was used originally as a bell tower, which was the purpose of all the other round towers in Ireland. However, it also ended up being used as refuge by monks during monastery attacks, along with others for storage and lookouts. What is very special about this tower is that the door is 3.5 meters above the ground, which helped those seeking refuge to help from within and also evade searches from attackers and those they are hiding from. Looking at the condition of this tower that is over 1,000 years old, it is obvious that it has served its purpose well throughout the centuries, looking at near perfect condition even until now. (http://www.megalithicireland.com/Glendalough%20Round%20Tower.html)

In “That the Science of Cartography is Limited”, poet Eavan Boland writes, “–and not simply by the fact that this shading of/forest cannot show the fragments of balsam,/the gloom of cypresses,/is what I wish to prove.” This is very reminiscent of the situation of this round tower. From the outside, all we can see is an old tower used by outdated material, wondering when it will crumble. What we fail to see, at first glimpse, is the many lives that this tower has saved, almost as if each life saved has added to the history and lifespan of this tower. That no matter how it looks, and its business in a graveyard, it had served an important purpose in historical Ireland and continues to do the same now as a bell tower.

Round towers and tall tales

Ireland’s only unique contribution to world architecture, the free-standing round tower, survives at some 65 sites with examples in all but four of the 32 counties of this island.

Their primary function was that of a belfry – the annals almost always label each one as a cloig-theach (bell house). They also had secondary functions. The traditional use of the round tower, taught to past generations, was one of defence, particularly during Viking raids on monasteries and churches. This supposed primary purpose has been long discounted, not only as almost all of the surviving towers postdate Viking times but also as they are virtual death traps in times of strife. That said, they would have been used for temporary refuge during sudden attacks.

More importantly, they were symbols of prestige, power and wealth, not only of the ecclesiastical community that built them but also of their patrons. Some acted as the treasure houses of the foundation, with the doorway or large second-floor window allowing relics to be displayed. Some may have acted as scriptoria, where monks write, copyied and illuminated manuscripts – although in most cases the poor light from the small windows would have been a hindrance. That they were sacred spaces seems most likely, but we may never know all of the towers’ functions.

The doorways of most face east, towards the west gable of the principal church. The ecclesiastical plaza this created was at the heart of the monastery and allowed pilgrims and other laity to participate in spiritual pageantry.

Surviving examples stretch from foundations only to tapering cylinders more than 30m high. Entered by a single doorway, usually high above the ground, these five- to seven-storey buildings had small windows, with wooden floors connected by internal ladders to the top storey. Here, under a corbelled, conical stone roof, at least four windows opened to the cardinal points, allowing the bell tones to ring out the canonical hours of the monastic day.

Apart from looking nice, the taper was a vital construction feature, stabilising the tower as it leaned in on itself. This cylindrical template survived for almost 300 years.

The type of stone used depended on local availability. At Roscrea, conglomerate sandstone was sourced locally, probably on Carrick Hill. Kilmacduagh has fine Burren limestone, and eastern examples, such as that at Castledermot, use granite. The quality of masonry depended on the wealth of the patron: Clonmacnoise, for example, has fine ashlar – large, square-cut stones – that only a royal benefactor is likely to have been able to fund.

These examples relate only to towers that survive, of course, and not to previous ones on the same sites. Clonmacnoise, for example, most likely had an earlier tower than the one recorded as finished in 1124.

The origins of the Irish round tower remain an open question. Were they copied from the towers of Ravenna, on the Italian Adriatic, which in turn could have had their origins in the minarets of eastern Europe and north Africa, which in turn had evolved from primitive lighthouses? Were they based on Anglo-Saxon examples or copied from the towers of southwestern Europe, specifically those found at the great centres of Christian pilgrimage?

The artist Hector McDonnell, who is also a keen historian and archaeologist, argues that the Irish idea for the free-standing tower came from Ravenna. “They were built in emulation of the very first bell-towers of Europe, which were erected in Ravenna in the ninth century, and they in turn were inspired by the erection of the very first true minarets, which appeared on the North African coast after the Islamic conquests of that area . . . It is a remarkable example of the cross cultural spread of simple but very important idea – the imposition of time keeping for worship in both Islamic and Christian communities through the broadcasting of the religious hours from high towers. Effectively, this is the beginning of the standardisation of time keeping which has remained ever since an important issue in all societies. We are therefore looking at monuments to something of extreme importance in the development of modern thought and science when we look at our round towers.”

It is easy to visualise a returning Irishman copying the basic concept of a round, free-standing belfry, but without the frills or architectural detail suitable only for a Mediterranean climate smaller and with far fewer windows, large stones instead of brick, and no tiles for the roofs.

So the absolute origin of the Irish round tower may have been the widespread use of belfries throughout the Christian world. The Ravennese bell towers, probably dating from the early 10th century, are strong contenders as prototypes for the Irish round tower, albeit with noticeable variations.

It would be difficult to find a monument anywhere in the world with such varied theories about its function or purpose. That they were belfries, as their Irish name indicates, exclusively erected at religious sites, is no longer questioned, at least by scholars, but their origins, functions and place in the monastic suite of church buildings remains debatable. A fashionable late-medieval theory was that they were built by the Danes as watchtowers that the Christian Irish converted to clock or bell towers.

They were also variously thought to have been fire temples, sundials astronomical observatories, Buddhist temples, phallic fertility symbols, launchpads for Druidic festivals, or a combination of all these. Other theories include penitential prisons, hermitages, and anchorites’ towers.

The art historian Peter Harbison suggests an important role for Irish round towers in the context of pilgrimage, pointing out that Rome, Jerusalem and Antioch all had round towers in the eighth century, as shown by the frescoes at the Old St Peter’s Basilica, in the Vatican City. He points to a 17th-century copy of these and suggests that Irish pilgrims may have brought the idea back home. By the 12th century, Harbison contends, the doorway of a round tower with an extended timber platform could have been used for the veneration of relics, an important part of the pilgrimage ritual.

Throughout the 1840s, amateur local archaeologists, under the influence of the noted Cork antiquarian John Windele, excavated at about eight round towers, including Roscrea. Finding skeletal remains at all of them, they surmised that their primary purpose was sepulchral: that they were “grave markers for great people”.

Against the backdrop of these arguments, the 1830s brought seminal research to the study of round towers. For some time the Royal Irish Academy decided to sponsor a competition for the best work about their origins and uses. The gold medal and £50 prize were won by George Petrie for The Origins and Uses of the Round Towers of Ireland, a paper he delivered to the academy in 1833.

Petrie undertook a detailed and painstaking rebuttal, indeed demolition, of the supposed evidence of the fanciful theories. He placed the towers firmly in an ecclesiastic and monastic context. “They are without a single exception,” he wrote, “found near old churches, or where churches are known to have existed.”

So when were they built? The dating of most of the towers is surmised mainly from the architectural evidence and from their ecclesiastical, topographical and political context. The building of a few is noted in the annals, although only Clonmacnoise, with 1124, has an actual completion date. Tuamgraney was built by 950 the structure at Annaghdown is recorded as being completed in 1238, although it is undecided whether that example was a round tower. Other round towers noted in the annals show their existence by the recorded date, and some of the surviving towers may be replacements. However, we are in the dark for a sound chronological listing.

The definitive number of Irish round towers surviving or known from antiquarian sources remains somewhat debatable. Some scholars do not accept attached towers, such as those at Glendalough and Clonmacnoise, as true examples. Others count them in. Nevertheless, a 65 is the accepted approximate number for intact towers, with evidence for about 25 more, but there are slight variations on these numbers from some scholars.

With most doorways well above ground level, probably to avoid weakening the base, access to the tower had to be by some kind of external stairs, either permanent or detachable.

In the past a rope or rigid ladder was the presumed entry method to what was popularly perceived as a place of refuge. Most of us grew up with the narrative sequence of surprise attack followed by a dash up a ladder, which was pulled in through the doorway by a petrified monk. But when one considers the agility required to scale a rope ladder or the implausable manipulation necessary to get a rigid one into a round tower, the difficulties are evident. It’s not a feat one would favour undertaking at the best of times, never mind while being pursued by an axe-wielding marauder.

Gerge Cunningham is the author of The Round Tower at Roscrea and Its Environs (Parkmore Press)

Round Tower, Glendalough, County Wicklow, Ireland. Drawn by W.H.Bartlett, engraved by J.C.Bentley. From 'The Scenery and Antiquities of Ireland' by N.P.Willis and J.Stirling Coyne.Illustrated from drawings by W.H.Bartlett. Published London c.1841.

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Round Tower, Glendalough - History

• Clondalkin Round Tower is approximately 1,250 years old it is a national monument and forms the historic heart of Cluain Dolcáin.

• Round Towers are a uniquely indigenous form of Irish architecture and the Clondalkin tower is acknowledged as the most perfectly intact example of these ancient structures. It is also one of the oldest intact man-made structures of any type in Ireland.

• The tower is built of local calp limestone which shows no sign of being worked or shaped by a mason. It is the most slender of all round towers in Ireland, being 27.5 mts (90ft 6ins) in height with a circumference of 12.7 mts (41ft 8ins).

• The buttress of small stones and rubble is unique, not appearing on any other tower. It was not part of the original structure and was built using different materials.

• In common with other round towers, the door is elevated above ground level (3.9mts) and the door, which faces east, is square-headed with four jambstones on either side. These stones, along with the sill and lintel, are of granite.

• There are six windows in the tower, one on the first floor facing south, one on the second floor facing west, and four just below the cornice facing the four cardinal points.

• The cap which sits on the cornice is reputed to be the original.

• The Round Tower is the subject of numerous drawings and paintings by famous antiquarians over the ages, including Samuel Molyneaux (1725) and Berenger and Wakeman (1843).

• The Tower is associated with 7th Century Saint, Crónán, the founder of the monastic site on which the Round Tower stands and is thought to have been built to house his relics.

• Modern Clondalkin is a vast suburban area yet the circular one-way system in the busy village follows the outline of the original monastic settlement of which the tower is a part.

• The tower is a source of considerable local pride and is a potent symbol of local identity, featuring in the logos of many Clondalkin organizations.

The Round Towers of Ireland

Scattered with a seeming randomness across the rolling hills of Ireland are the remains of sixty-five round towers. Soaring as high as 34 meters above the ground, the towers are in remarkably fine condition considering the antiquity of their construction. When exactly the towers were constructed is unknown. Scholars have suggested that the most probable construction period was between the 7th and 10th centuries AD, and this hypothesis is based on the fact that nearly every tower is at the site of a known Celtic church dating from the 5th to 12th centuries. Initially each of the towers were freestanding structures but in later times other buildings, primarily churches and monastic foundations, were constructed around some of the towers.

Thirteen towers retain a conical cap and it is assumed that all the other towers once had similar caps that have fallen over the centuries. On a small number of towers battlements have been built on to the top but it is known that these battlements were added at a later date in the Middle Ages. The principles used in construction of the towers is always the same: two walls of block and mortar construction are built a few feet from one another and the space between is filled in with a core of rock rubble. This was a standard method of wall construction utilized by the Romans. Scholars believe that Christian missionaries learned the technique in England or continental Europe and then brought the building technology to Ireland, incorporating it in the building of the massive round towers.

Writing of the dimensions of the towers in his book, Irish Round Towers, Lennox Barrow states: "It is remarkable how little the main dimensions vary. In the great majority of towers the circumference at the base lies between 14 meters and 17 meters and the thickness of the wall at the lowest point at which it can be measured varies from 0.9 meters to 1.4 meters. Doorways, windows, storey heights and diameters also follow clearly defined patterns, and we may well conclude that most of the towers were the work of teams of builders who moved from one monastery to another using standard designs." Barrow goes onto say that: "Most doorways are raised1.5 meters to 4.5 meters above the ground.This is usually explained as being for security, to enable the monks to take refuge inside the towers during times when Viking raiders or bandits were attacking the monasteries. There is probably some truth in this theory but t is possible that the stability of the tower had as much to do with the door heights. The higher you could build before making an opening in the wall the stronger the base would be. Very often the towers were filled in, even as high as the doorways."

This idea that the round towers were erected and used primarily as watch towers and places of protection is strongly debated by an American scientist, Philip Callahan. Writing in his book, Ancient Mysteries, Modern Visions, Callahan discusses research which indicates that the round towers may have been designed, constructed and utilized as huge resonant systems for collecting and storing meter-long wavelengths of magnetic and electromagnetic energy coming from the earth and skies. Based on fascinating studies of the forms of insect antenna and their capacity to resonate to micrometer-long electromagnetic waves, Professor Callahan suggests that the Irish round towers (and similarly shaped religious structures throughout the ancient world) were human-made antenna which collected subtle magnetic radiation from the sun and passed it on to monks meditating in the tower and plants growing around the tower's base. The round towers were able to function in this way because of their form and also because of their materials of construction. Of the sixty-five towers, twenty-five were built of limestone, thirteen of iron-rich, red sandstone, and the rest of basalt, clay slate or granite - all of these being minerals which have paramagnetic properties and can thus act as magnetic antenna and energy conductors. Callahan further states that the mysterious fact of various towers being filled with rubble for portions of their interiors was not random but rather may have been a method of "tuning" the tower antenna so that it more precisely resonated with various cosmic frequencies.

Equally intriguing, Callahan shows that the seemingly random geographical arrangement of the round towers throughout the Irish countryside actually mirrors the positions of the stars in the northern sky during the time of winter solstice. Archaeological excavations at the bases of the towers have revealed that many towers were erected upon the tops of much older graves and it is known that many of the tower sites were considered sacred places long before the arrival of Christianity in Ireland. These facts compel us to wonder if the ancient Irish, like the Egyptians, the Mayans and many other archaic cultures understood there to be an energetic resonance between specific terrestrial locations and different celestial bodies. This certainly seems to be the case. All across the Irish countryside particular locations were chosen, precisely designed structures were erected to gather and store various energies, and a tradition of humans' spiritual use of the sites arose over the millennia. While many of the round towers are now crumbling and therefore their antenna function may no longer be operative, a field of holiness still permeates the sites today.

In another article (The Mysterious Round Towers of Ireland: Low Energy Radio in Nature The Explorer's Journal Summer, 1993) Callahan gives further details of his discoveries:

"Most books will tell you that the towers were places of refuge for the monks to hide from Vikings raiding Ireland. They were, no doubt, bell towers and lookouts for approaching raiders, but the speculations that monks escaped raiders, who no doubt knew how to smoke bees out of hives or climb the 9 to 15 feet to the door, borders on the ludicrous. Round towers are perfectly designed to be totally useless for hiding people or church treasures. Another strange thing about the towers is the dirt that fills the base below the high doors. Each door has a different level of dirt filling the base as if they were "tuned" like a pipe organ. I had long postulated that the towers were powerful amplifiers of radio resonance from the atmosphere generated by lightning flashes around the world. The round towers proved to be powerful amplifiers in the alpha brain wave region, 2 to 24 Hz, in the electrical anesthesia region, 1000 to 3000 Hz, and the electronic induction heating region, 5000 Hz to 1000 KHz. It is fascinating that just above the surface of the ground to about 2 to 4 feet up there is a null of atmospheric frequencies that get stronger and stronger until at 9 to 15 feet above the surface they are extremely strong. The Irish monks were well aware of this for that is where they built their high doors. At every tower we measured there was a direct correlation between tower door height and the strongest waves. That the highly amplified waves occur in the meditative and electrical anesthesia portion of the electromagnetic spectrum is of utmost significance. In 1963, G. Walter researched brain EEG waves from 0.5 to 3 Hz (Delta region) and found anti-infectious effects. There is an elegant but short list of research projects demonstrating the beneficial effects of low ELF wavelengths on sick people."

Round tower of Cashel

Jutting high above the plain of Tipperary against the backdrop of the Galteemountains is the 28 meter round tower of Cashel. While the tower dates from the 11th century, the rock outcrop upon which it stands has fortifications from the early 4th century when itwas the stronghold and ceremonial center of a powerful clan. Patrickis said to have visited the site in450 AD and hence one of its popular names, St. Patrick's Rock.

Round Tower of Glendalough

The tower of Glendalough is considered by scholars to be the most finely constructed and beautiful tower in all Ireland. Situated in the cleft of a steep and thickly forested valley, the 30 meter tall tower is built of mica schist with a granite doorway. Glendalough was an ancient gathering place of pre-Christian hermits and the first Christian monastery was established by St. Kevin who lived in the enchanted valley from 498-618 AD. Clustered about the base of the tower are remains of a 1200 year old cathedral and the first functioning university in the western world. Nearby the tower is the healing cross of St. Kevin. A local legend states that if one encircles the cross with one's arms and makes a wish concerned with healing, that wish will be fulfilled according to the depth of one's love of God.

Round Tower of Glendalough, Ireland

Hugging the miraculous healing cross at Glendalough, Ireland

Round Tower of Kilmacduagh

Kilmacduagh, north of Limerick in county Galway, is the tallest of the Irish towers at 34 meters and, while quite stable, appears to be tilting precariously. Little is known of the adjoining monastery, probably founded in the early 7th century, and it is assumed that the round tower was erected sometime in the 10th or 11th centuries.

Round Tower and monastery of Kilmacduagh, Ireland

Detail of Round Tower of Kilmacduagh, Ireland

Clonmacnoise Round Tower, Offaly

Clonmacnoise Round Tower, Offaly

Ardmore Round Tower, Waterford

Scattery Island Round Tower, Clare

Martin Gray is a cultural anthropologist, writer and photographer specializing in the study and documentation of pilgrimage places around the world. During a 38 year period he has visited more than 1500 sacred sites in 165 countries. The World Pilgrimage Guide web site is the most comprehensive source of information on this subject.

Drumlane Abbey and Round Tower

The church and round tower at Drumlane have been in the care of the Office of Public Works for the past 138 years. The disestablishment of the Church of Ireland in 1869 resulted in the transfer of 139 architecturally important ecclesiastical structures to the ownership of the Commissioners of the Board of Works. These National Monuments included such well-known sites as the Rock of Cashel, Clonmacnoise and Glendalough. Drumlane Abbey and Round Tower were the fourth to be listed in the first register of National Monuments. By the end of 1880, the Board of Works had appointed the well-known architect, Thomas Deane, as Inspector of National Monuments and began conservation work on the churches at Clonmacnoise and Glendalough. Following the political upheavals of 1921, the Board of Works was the only Government Department to remain largely unchanged under Saorstát Éireann (the Irish Free State) and the conservation of National Monuments continued under their remit.

I joined the National Monuments Trim district in 2002 having previously worked in the Mallow district. The District Works Manager of the time, Tom Spears, brought me to see the church at Drumlane which is located on the shore of Garfinny Lough. The gable of the church ruin dominates the round tower and tranquil cemetery. On that first visit, we came to inspect the large eastern gable wall of the church which appeared to be gradually moving away from the two side walls, slipping slowly towards the lake. The presence of a series of large buttresses against the outside of the long side walls indicated a long history of structural instability. In an early image of the church, dating from 1792 in ‘The Antiquities of Ireland, Volume 2’ by Francis Grose, the church has a large steeply pitched roof which must have exerted a tremendous outward thrust on the long side walls. The buttresses were already in position in 1792 to provide additional stability and prevent the roof from causing the side walls to collapse. The outward pressure on the side walls was reduced when the roof perished but the gable wall was then fully exposed to the weather and began to deteriorate. We installed crack monitors and over the following years regularly inspected the gable wall for signs of active movement. In March 2014 Kieran Walsh of the OPW Structural Engineering Section, and I carried out a more detailed inspection from a hoist in order to assess the condition of the large vertical cracks at the junction of the east gable and the two long side walls of the medieval church. The inspection confirmed that the gable wall had moved and was in need of stabilisation works. The project was included in our 2014 business plan and works began in June of the same year.

The first part of the project was the protection of the grave slabs near the east gable, enclosing them in timber covers. We then erected a scaffold around the gable wall to facilitate the works. We were able to examine the masonry work at close quarters and do some preliminary opening up work. The cracks did not extend fully to ground level so there was no indication of a structural problem with the foundations. The cracks widened as they moved further up the wall, confirming that the gable of the church was not strongly bonded to the two long flanking walls and had moved away from them. Without the protection of a roof, walls will develop problems due to the constant movement of water through the structure. The mortar bond between the stones is gradually washed out until there is little structural integrity left in the masonry.

The OPW stonemasons carried out the consolidation works to the gable, working during the summer months when the days were long and the temperatures suitable for lime mortars. We rebuilt large sections of the walls, particularly around the areas that had moved out of position. The rebuilt masonry was strengthened with stainless steel ties to ensure a good joint with the existing walls and the entire gable was repointed. As the works proceeded upwards, a lime based grout was introduced into the walls to ensure that all the internal voids were filled and stable. Finally, the wall tops were flaunched to ensure that the rainwater ran smoothly off the walltops. Works were completed in April 2017 and the enclosing scaffolding cover was left in place for an additional year to assist with the curing of the lime mortars and grout.

We are now confident that the gable wall is stable and the future of this important ecclesiastical assembly is secure. OPW Trim National Monuments staff will continue to monitoring the condition of the buildings and maintain the church and round tower. We will assist the Department of Culture, Heritage and the Gaeltacht in their role of conserving Ireland’s unique heritage for the benefit of present and future generations. The works on site were supervised by Tommy Halton, District Works Manager and carried out by Michael Dempsey, Willie Foley, Eamon Gilsenan, Ger Doherty, Brian Murray, Eamonn Howley, Brendan Hussey, Willie Hussey, Derek Caroll, Thomas Donnelly, Mark Leavy and Ger Brennan.

Ana Dolan worked as a Senior Conservation Architect with the Office of Public Works until her retirement in 2020.

Globetrotting Vikings: The Raiding of Ireland

Not even St. Patrick himself could protect Ireland from the Vikings. When the Nordic raiders launched their first attack on Ireland in 795 A.D. by raiding an island monastery, Irish monks wielded prayers in self-defense. No heavenly intercession arrived, however, to save their cloister from being sacked.

The Vikings continued to stage small hit-and-run raids on unprotected coastal monasteries before sailing up the River Shannon in the 830s to plunder inland religious settlements. The foreign invaders even defiled Ireland’s holiest turf by plundering the monastery of St. Patrick at Armagh, slaughtering its monks and desecrating the buildings erected in honor of Ireland’s patron saint.

A Viking longship is beached on the lake shore at the Irish National Heritage Park. (Credit: Richard Cummins)

While it was the Danes who attacked England and Francia, it was mostly the Norwegians who raided Ireland. By the 840s, those Vikings began to establish permanent ship bases along the coastline from which they could plunder year-round. Coastal enclaves at Dublin, Wexford, Waterford, Cork and Limerick became trading centers for Ireland’s treasures𠅊nd its people.

According to John Haywood, who chronicles the exploits of the Scandinavian raiders on four continents in his new book, “Northmen: The Viking Saga AD 793-1241,” slavery had been rare in pre-Viking Ireland, but that all changed with the arrival of the Norwegians. “The Vikings milked Ireland fairly systematically for a couple hundred years for slaves. Dublin originated really as a slave market,” he says.

At first glance, Ireland appeared to be ripe for a complete Viking conquest. After all, the Vikings took advantage of internal divisions to seize England and Francia, and Ireland was the most politically fractured country in Western Europe, according to Haywood. A complex hierarchy of 150 local kingdoms and a dozen over-kingdoms ruled the island, and even high kings only directly ruled over small territories. Furthermore, Irish kings often welcomed the incursions of the foreign invaders as a means to weaken their domestic rivals.

The round tower at the Glendalough monastic site in Country Wicklow, Ireland. (Credit: Peter Zelei Images)

Yet, while the Vikings had success raiding Ireland, they failed to conquer the island as they did other lands in Europe. “It looks like there could be a Viking takeover, but it’s pretty clear by the middle of the 10th century that apart from fortified enclaves along the coast, they have failed absolutely to control territory in Ireland in the same way as they did in England, Scotland, France or Russia. If they don’t have forts around them, the Vikings can’t really survive in Ireland.”

Haywood says Ireland’s decentralized system of governance, which made the island appear vulnerable to a larger force, actually had the opposite effect in protecting it from a Viking takeover. He points out the the centralized kingdoms of early medieval Europe were the most easily conquered since there was a much smaller ruling class to either eliminate or negotiate with to forge a lasting peace agreement. With so many kings to subdue and bargain with in Ireland, it proved much more difficult to eliminate or co-opt the existing power brokers.

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Watch the video: The Round Tower, Glendalough (January 2022).