The Round Towers of County Offaly. By John Dolan

It is unclear where the idea for a Round Tower came from, little research has been carried out on their origins. There were a few examples of cylindrical towers in northern Italy, the Basilica of San Vitale in Ravenna is an example. European churches had started to connect bell towers and crypts to their churches between the 900 – 1,100AD. These towers were built stand-alone and later joined to other church buildings. But European bell towers were nearly all rectangular.

What was happening in Ireland?

In Ireland churches continued to be built as small rectangular buildings, single celled with one doorway and perhaps a window or two. Irish church buildings changed from wood to stone during the 8th century. However, monasteries blossomed as locations of education, agriculture, metal and wood working, vellum production, with their skills retained in-house or shared with other church establishments. External trade and travel with Europe were a regular occurrence. Most monasteries had wealthy, secular sponsors who were frequently related to the abbot or bishop. Monasteries also acquired lands and other riches e.g., wealth from pilgrimages and relics.

Round Towers enhanced the prestige and wealth of the monastery as they created a huge visual impact. Round Towers were to see and be seen, similar to some of the buildings built in the time of the Celtic Tiger.

Offaly Round Towers

According to the National Monuments database there are three Round Towers in County Offaly, two at Clonmacnoise and one other at Saighir (Seir Kieran), Clareen. However, Elizabeth FitzPatrick has suggested that there are two more potential sites at Durrow and at Kilclonfert but no evidence survives overground.

The main tower at Clonmacnoise is circular and five storeys high, is known locally as O’ Rourke’s tower. The top storey which was rebuilt in the modern period has 8 rectangular slits. There is a door at the first-floor level, facing south east. The conical cap was destroyed (see below), and there were wooden floors at every level.

Many of the Round Towers were built with the door of the tower facing the door of the cathedral.  It is speculated that the main reason for this was to allow the bishop address his flock on the main religious festivals, display the relics in the church or display the monstrance.

Round Tower aligned with cathedral front door

Clonmacnoise example

(For references in the Annals the following keys apply: AFM = Annals of the Four Masters; AU = Annals of Ulster; CS = Chronicon Scotorum; Annals of Tigernach =AT; Annals of Inisfallen = AI. All of the references are taken from translations in the UCC online database at You will note that the word cloigteach – bell-house is spelt in a variety of ways in the Annals).

The construction of the cathedral was recorded in this entry in the Annal entry CS909 ‘the cathedral of Cluain moccu Nois was built by Flann son of Nael Sechnaill and Colmán Conaillech’.  The Annals record the completion of the tower; in 1124AD it reads ‘the finishing of the cloicteach of Cluain-mic-Nois by Ua Maeleoin, successor of Ciarán’.

Trouble arrived for the Round Tower as this entry related in AMF1135 Lightning struck off the head of the Cloictheach of Cluain-mic-Nois, and pierced the cloictheach of Ros-Cre.  The event is supported by this watercolour drawing by George Petrie around 1838, now in the National Gallery. The damage recorded by Petrie has been remodelled somewhat, mainly by antiquarians during the 1800s.

Between 832 and 1204, Clonmacnoise was attacked thirty-three times and finally reduced to ruins by the English in 1552 as recorded by Petrie ‘Clonmacnoise was plundered and devastated by the Galls (English) of Athlone, and the large bells were carried from the cloicteach. There was not left, moreover, a bell, small or large, an image, or an altar, or a book, or a gem, or even glass in a window, from the wall of the church out, which was not carried off. Lamentable was this deed, the plundering of the city of Ciaran, the holy patron.”

The second Round Tower at Clonmacnoise is attached to a church. This round tower is six storeys high and is completely intact with conical cap. The tower is accessed from the chancel of the church and had wooden floors at each level lighted by a window on the south east side.

The church of Temple Finghin with its tower was certainly built before 1015AD as this entry in the Chronicon Scotorum for 1015 recounts ‘a great wind in the autumn to which no parallel has been found in this time, in which the great oak of the Recles of Fingin in Cluain moccu Nois fell’.

This second Round Tower at Clonmacnoise is called an engaged tower, there are a small number of these towers in Ireland.  St. Kevin’s church in Glendalough is probably the best-known engaged tower. Here are some:

The third Offaly Round Tower is at the site of St. Ciarán’s monastic site at Clareen outside Birr. As mentioned earlier, this site is presumed to be one of the earliest Christian locations in Ireland.  Recent geophysical scans of the site have only revealed medieval earthworks. It would appear that the Round Tower is the oldest surviving building on the site, even though only the stump of the tower now remains.

Round Tower base, Seir Kieran

Seir Kieran Round Tower

Irish Round Towers.

Lalor 1997 map of Ireland's Round TowersThere are 86 Round Towers surviving today.  The majority were built between 900 – 1,100AD.  Nearly all are associated with early church sites. The earliest mention of a Round Tower in the Annals is from AU950 ‘the bell-house of Sláine (Slane) was burned by the foreigners of Áth Cliath.  The founders episcopal staff, and the best of all bells, the lector Caenachair and a large number with him, were all burned’.  This would not be the last time that Vikings would lay destruction on Irish monastic sites.

Details from annalistic and manuscript references suggest that 25 Round Towers have disappeared off the landscape.

As with other early artefacts, such as Ogham stones, crannoga and Sheela-na-Gigs Round Towers were built outside Ireland – perhaps over half a dozen were built in Scotland, mainly in the Scottish Isles.

Antiquarian ideas about Round Towers.

During the 1800s and earlier, antiquarians speculated on the various reasons why Round Towers were constructed.  Many publications offered a wide range of options, some of these were:

  • That the Phoenicians erected them for fire temples.
  • That the Magicians used them for astronomical purposes.
  • That they were for Christian anchorites to shut themselves up in.
  • That they were penitentiaries.
  • That the Druids used them to proclaim their festivals.
  • That the Christians used them to keep their church plate, relics and treasures.
  • Prestige! Wealth!  Show Off!! Hugh visual impact
  • Summon the monks from the fields, announce time for prayer – timekeeping essential in the religious life
  • Display shrines/relics at time of pilgrimage
  • Security for community or refugees
  • Grain storage (if properly sealed)
  • Lookout

A paper by Rev. John Milner, however, did not believe that they could be bell towers for he writes ‘none of these towers is large enough for a single bell of a modern size to swing round in it.. .and from the smallness of the apertures in them, they are rather calculated to stifle rather than to transmit.’


No bells have been found in Round Towers or on monastic lands.  There is no evidence that the upper floor contained the necessary wooden structures to hold the large bells associated with today’s church towers/steeples.

The Brehon Law mentions two grades of bell ringers, there was considerable prestige attached to his position ‘Noble his work when the bell is that of the clocthech, humble his work when it is a hand bell’.  There are suggestions that bells were used for agriculture and liturgical purposes.  However, there is evidence that the early church did use hand bells and these are the most likely to have been used in the towers.

Many monasteries had skilled metal workers and the metal residue has been found where the works were carried out in places such as Gortnahown and Mitchelstown.  Whereas there has been no mention, or idea of shape/size of tower bells a number of suggestions have been made.  There include hand bells made from iron with a coating of copper-alloy along with small bells made from a single cast measuring 80mm – 100mm high.  Larger bells may have been riveted and measured 140mm – 310mm high. The bells below are speculative drawings from antiquarian sources.

Examples of early Irish bells

Early Irish bells

Some bells were treated as relics and were enshrined and held for veneration at a time of pilgrimage.  Founder missals and croziers were also held for such veneration.  A particularly local reference to a bell is that of Bardán Chiaráin of Saighir (Seir Chiarán). This is the bell given to Ciarán by Patrick on Ciarán’s return to Ireland; it is the bell that rang to identify to Ciarán where to establish his cell/monastery. The location today is known as Bell Hill and overlooks the ancient monastic site at Saighir, Clareen, Co. Offaly.  Rev James Graves in his 1857 account on the history of Kilkenny Cathedral says of Ciarán’s bell that ‘it was universally honoured throughout Ossory, being carried to the treaties of princes, sworn on for a defence of the poor, and used to sanction the collection of the tribute to the monastery by the people of Ossory’. The word bardán is an old Irish word meaning gapped, the bell had been cracked at one stage.

Don’t hide here!

There are at least six accounts from the annals of Round Towers been burned down, but not accidently.  The first recorded burning was that at Slane, as mentioned earlier.

Dangerous Places.

Some affected by war – don’t hide here!

AT996 Cairell’s son, with the men of Farney and Oriel, plundered Armagh and carried off two thousand cows, that is, Armagh was burned, both houses and stone-house and belfry, and sacred wood—a ruination that had never occurred in Ireland, and vengeance like that will not occur until Doomsday.

AFM1050 Doire-Caelainne and the Cloictheach of Ros-Comain were burned by the men of Breifne.

AFM1076 Murchadh, son of Flann Ua Maeleachlainn, at the expiration of three days and three nights after his having assumed the supremacy of Teamhair, was treacherously killed in the Cloictheach of Ceanannus, by the lord of Gaileanga

AFM1156 Eochaidh Ua Cuinn, the chief master, was burned in the cloictheach of Fearta

AFM1173 The Cloictheach of Telach-aird was burned by Tighernan Ua Ruairc, with its full of people in it.

Others were affected by weather:

AFM995 Ard-Macha was burned by lightning, both houses, churches, and cloictheacha, and its Fidh-neimedh, with all destruction

AFM1015 Dun-da-leathghlas (Downpatrick) was totally burned, with its Daimhliag and Cloictheach, by lightning.

AFM1039 The Cloictheach of Cluain-Iraird (Clonard) fell.

AI1285 A very destructive wind this year about the Feast of Brigit [February 1].: it blew down the bell-tower of Ros Ailithir and caused much damage generally.


Only a handful of Round Towers have been excavated, none recently.  Antrim, Armoy and Lusk were excavated in the 1840s but no reports are available.  Kilkenny was also excavated and report notes are available. These excavations were carried out by antiquarians who may have used a common standard of work, or may not.

Both towers at Clonmacnoise were excavated. What we have today is a four and a half page report read to the Proceedings of the Royal Irish Academy (1844 – 1847), by Colonel Harry D. Jones but he does not give us an actual date that the excavations were carried out.  The report itself is poorly structured so it is difficult to identify which tower he is referring to at times.

Each tower had a separate group of diggers. The fill inside each tower was up to the door sill. The plan was to dig down until the natural ground was reached. Most of the interiors were filled with vegetable matter, comprising wood, twigs mixed with birds’ nests; also stones that had been thrown in. At a depth of 3 ft and 9 inches in one of the towers the ribs of a skeleton were found. However, the bones broke into fragments when touched. Digging further, a skull was found ‘in a perfect state’.

Removing the first skeleton a second skeleton was found one foot lower. These bones also proved brittle and fell apart when handled.  It appeared that both bodies had been buried in the tower naked as no remnants of wood or clothing were found.  As well as human bones there were bones from birds, sheep and pigs in the fill.  When the excavation was completed all the material was replaced back into the towers, as was the standard of the time.

Drawing of Kilkenny Round Tower skeletonsThe Kilkenny excavation was of a higher standard and produced a 20-page detailed report by Graves and Prim in 1875, including this fine drawing of the two adult and one child (in a coffin) skeletons found buried underneath the tower.  The bodies were dated to 990AD while the tower was probably built 200 years later.

In the second half of the last century a number of exploratory trenches were dug outside of over a dozen Round Towers.  Most of these digs were to investigate the base of each tower and the construction techniques deployed by the builders as the foundations appeared to be so shallow.  These included towers at Inis Cealtra and Roscrea.  Again, a high number of skeletal remains were found close to the towers.

Why did they die out?

Round Towers fell out of fashion with the arrival of Continental monks, led by those brought in by St. Malachy and St. Bernard of Clairvaux.  The incoming monks and nuns, along with three or four major synods were all part of major church reform in Ireland in the 1100s.

The first major establishment of these Cistercian monks was at Mellifont, Co. Louth in 1142AD.  Not only did the monks bring monastic rules on how they should live and different agricultural skills but they also introduced European architecture styles for both church and monastic sites.

This European development was a revolution in Irish church architecture, bringing the Romanesque style of building churches never seen here before.   No new Round Towers were built after this time.