The one at Cloonback, in County Longford, has had a road cut along its northern edge and a house built into its south-eastern arc, yet the essential shape of the thing survives, sitting on a high, prominent hill from which you can see in every direction. That elevated position is itself a clue to how seriously this place was once taken.

A ringfort, or rath, is an enclosed farmstead of the early medieval period, typically dating from roughly the fifth to the twelfth century. Most consist of a raised circular platform, an enclosing earthen bank, and a surrounding ditch. The Cloonback example follows this pattern with some solidity: the raised interior measures just under 35 metres in diameter, and the bank of earth and stone around it runs to more than six metres wide and nearly a metre high. Beyond the bank lies an external fosse, a defensive ditch, that is nearly five metres wide and over a metre deep in places, and remains waterlogged. Along the western and north-western outer edge of the fosse, a low field bank is still visible. The original entrance has not survived in any recognisable form, so where people once passed in and out is now a matter of guesswork.

The modern roadway that abuts the northern side of the fosse has caused some infilling, as has the construction of the house to the south-east. These intrusions are not unusual for a country that has always lived alongside its archaeology rather than behind a fence. What the Cloonback rath retains, despite all of this, is its commanding hilltop presence, which probably explains why someone chose to build here in the first place, and why the outline has proven durable enough to read from the ground more than a thousand years later.