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)