Local History with Monica McGill – Tower is a unique part of our history, heritage and landscape

The Round Tower on Tower Road, Clondalkin is the only surviving original building associated with the Celtic Christian monastery founded here by St Crónán Mochua, who died in 630AD.

The Tower is a unique part of our landscape, history and heritage, yet familiarity makes it easy to take it for granted.

Historians say the Round Tower in Clondalkin was built about a thousand years ago, that it’s the slenderest and possibly one of the first.

It’s the only one with its original conical roof, and with a “skirt” or buttress at its base. Sporting no fancy decorations, the Tower’s surfaces are rough, unlike Round Towers of a later date.

The Tower has one doorway, facing east. The door of a Round Tower usually faces the same direction as the main altar of its accompanying church – that is, eastwards.

Our Tower’s 6 windows face the cardinal compass points of North, South, East and West. Long wooden ladders connected the internal floors. A head for heights, sure footing and a steady hand were needed.

Together, the church building and Round Tower were the most important buildings in early Celtic Christian monasteries, forming a nucleus surrounded by a number of almost-concentric enclosures. Clondalkin’s Round Tower partnered the Church of St Crónán, once situated where St John’s Church is now.

Later, Tower Road was built, dividing the Tower from its church. Maps from the 1800s show that Tower Road was called Steeple Street back then, named after the Round Tower but using an old-fashioned word.

Schoolchildren were once taught that people and valuables were hidden in round towers whenever Vikings invaded, but now experts say it was a bell-tower (cloig theach in Irish) and a place to keep the precious belongings of St Crónán.

Clondalkin’s Tower is built of local calp limestone, extracted with skill and determination from nearby quarries.

The limestone was hauled to the site and, presumably, horses would have been used in this work.

On site, the heavy stones had to be raised ever higher as the cylindrical tower reached the required height and shape at each level (course) of stonework. Then the cap was built on top.

No-one knows whether scaffolds, pulleys or earthen ramps were used to raise the heavy limestones, nor indeed who the builders were.

There’s not just one Tower – there are two – one is inside the other. The gap in between was filled with rubble making the Tower much stronger than if it had only one “skin”. Just as well. In the 1700s the nearby gunpowder mill exploded causing widespread damage, but the roundness of the Tower saved it.

Some think the unique buttress was added at its base at about this time. Unfortunately, the squarer-shaped medieval church of St Crónán didn’t survive the explosion. There is only a piece of it left today, behind St John’s Church.

Mortar is the “glue” holding the stones of the Tower in place. This mortar included cattle blood to strengthen it, probably taken from local cattle.

Clondalkin rests on limestone, producing great feedstuffs for all sorts of farm animals, so it’s plausible that cattle would have been nearby.

A great number of extra workers would have been needed to help when the Tower was being built.

Everyone would have to be fed and accommodated around this very busy building site – quarry workers, hauliers, “blocklayers”, toolmakers and menders, mortar-makers, people preparing all the meals (and doing the washing-up!) and others who took care of the farm animals. The River Camac nearby must have been a good source of water.

Along with taking care of other people’s spiritual needs and their own, St Crónán’s monks here fulfilled other obligations.

At least one of the monks would have been an early physician or General Practitioner. His special knowledge was needed to take care of sick people, using medicinal plants purposefully grown in the monastery garden.

Even a thousand years ago, presumably people would have had coughs and colds, headaches, fevers, upset tummies, strains, sprains and broken limbs – as well as the industrial accidents that must have happened when the Tower was being built. There were no Health and Safety rules then.

The Round Tower, from St John’s
Photo Monica McGill

Some monks specialised in another task in the monastery’s Scriptorium, where the Bible and Books of Psalms and Hymns were copied onto

specially-prepared materials like calf-skin.

When very few were literate, these monks were fluent in three languages – Irish, Latin and Greek. The Karlsruhe Library in Germany contains a fragment of a Psalm-book.

The words are in Latin, but using Irish letters – a very early example of Irish script.

The transcribing monk wrote about St Crónán in the margin, naming the saint’s father and some other details. This led to the conclusion that the fragment – and the book it came from – was written in Clondalkin.

Celtic monks were expert at creating accurate calendars, especially calculating the true date of Easter – still the most important Christian celebration.

Easter Sunday is a moveable feast and calculating its occurrence involves observing the lunar cycle. Were Clondalkin’s monks involved in these calculations too?

Unfortunately, the astronomical work of the Celtic monks disagreed with other church experts who sided with Rome and the rest of Christian Europe.

Despite the forthright arguments of the Celtic side, the Synod of Whitby in 664 decided against them because, as one abbot favouring Rome remarked: “… a few men in a corner of a remote island should not be preferred before the universal Church of Christ throughout the world.”

Despondent and annoyed, it seems Celtic monks obeyed the decision.