Measuring 26 metres from northeast to southwest and 11 metres from northwest to southeast, this small island appears to have been deliberately constructed from stones, though it may rest upon a natural rock foundation. The northern end features a partially submerged stone wall standing 0.8 metres high and spanning 1.3 metres in width, whilst another probable wall cuts directly across the centre of the island, dividing it neatly in two.

This structure is what archaeologists recognise as a crannog; an artificial island dwelling type that was particularly popular in Ireland from the Early Medieval period onwards. Crannogs were typically built by laying down layers of stone, timber, and earth in shallow lake waters, creating defensible homesteads that were accessible only by boat or causeway. The strategic placement of this example in a small lake surrounded by low hills would have provided both protection and a commanding view of the surrounding landscape.

The site at Cashelenny represents one of many such structures scattered across Ireland’s lakelands, offering a tangible connection to how communities once adapted their living arrangements to make the most of natural defences. Though now silent and partially reclaimed by the waters, these stone remnants continue to mark the spot where families once lived, worked, and sought refuge on their constructed island home.