The Irish round tower – we all have a mental picture of it, a tall, finger-like stone erection in the middle of nowhere, reaching for the heavens and forming part of Ireland's tangible cultural heritage. And though all towers are different from each other,a number of common elements can be noted. So, what makes a typical round tower?
Height – A Perfect Hundred FeetOne of the defining characteristics of the round tower it its height, in fact the towers would have been the tallest buildings in Ireland for a long time. The average height is 29.53 metres. And this would be about right for 100 Roman feet. And as 100 is a “perfect” number, there might be even an esoteric implication here ... though this would seem a bit far-fetched to most people. Anyway: Irish round towers are just under thirty metres tall on average.
Circumference – Just About HalfThe circumference of the round towers' base works out at 15.63 metres on average, but no neat mathematical “secret” is hidden here. But an easy calculation would be to make the tower not higher than double the circumference of the base. This would ensure a relative stability with an easy-to-remember formula. Unless you mess up the foundations ...
Foundations – The Shallow BottomUnfortunately the builders of Ireland's round towers seem to have seen foundations as a cost-cutting exercise and kept them shallow, often around sixty centimetres on unstable or even boggy ground. They were also barely wider than tower itself. The medieval annals consequently mention a number of round towers that simply toppled over.
The Tower Taper – Narrowing to the TopWhile most Europeans built “straight up” at the time, the Irish constructed their round towers with a slight taper towards the top. This distributed the immense weight of the walls in such a way that the tower held itself up. There are exceptions to this rule – the round tower of Clondalkin is actually thicker around the middle.
Pugholes – A Necessary EvilOn many round towers stones of a different colour or workmanship can be seen at fairly regular intervals. These are not primitive decorations but serve to hide “pugholes”. These are actuals holes in the outer surface where scaffolding would have been anchored during the building phase. In some towers you can even see the pugholes proper, as the stones filling them in have fallen off.
A High Door – High Up That IsRound towers have no doors at ground level, the entrance always was higher up and could only have been reached with stairs, a ladder, a rope or by extreme pole-vaulting. This kept unwanted visitors out, but must have been awkward on a day-to-day basis. Some historians have suggested that wooden stairs would have been the most sensible addition, easily dismantled in an emergency.
Let There Be Light – Windows in the TowerThe interior of the round tower had several levels, made from wooden platforms and connected by ladders. To provide at least a bit of daylight, small windows were left at each level. One or two at the most. If we speak about “windows” here, we mean rectangular holes, not a fancy glass job.
The Bell Floor Windows – In the Room at the TopThe exception was the uppermost level of the round tower, were four larger (though not massive) windows, usually oriented towards North, East, South and West. They are called “bell floor windows” because more than likely they served to let the sound of a bell carry over the surrounding area. This bell may have been hand-held and certainly was small.
The Conical Top – Keeping the Rain OutRound towers were topped by a conical stone cap, expertly fitted by highly qualified stonemasons. As this was “high tech” at the time, earlier round towers may have had a less sophisticated cap made from wood or other roof coverings on wooden rafters. Some round towers “missing” their stone caps today may actually have had only the “low tech covering”.
There Goes the Neighbourhood – The Monastic District
Round towers were never an end to themselves, they were always part of a monastic settlement that would have included churches, living quarters, some utility buildings and often a high cross, where the masses assembled for mass. Today these may be gone, but a churchyard or church will usually be close and indicate the former monastery's grounds - like in Kells
Its All About Timing – The Round Tower in Historical Context
Round towers were built between the 10th and the 12th century over a period of roughly 250 years. That is to say the “Original Irish Round Tower” must be from that area, otherwise it is more than likely not a card-carrying “real thing”. Later towers can be found – the most impressive being the larger-than-life erection commemorating Daniel O'Connell in Dublin's Glasnevin Cemetery
And Finally – Location, Location, Irish Location
An Irish round tower has to be in Ireland – in fact only few examples of round towers similar to the Irish towers are known. One on the Isle of Man
(Peel), one in the Orkneys
(Egilsay) and two in Scotland (Abernethy and Brechin).