The monument consists of a substantial flat-topped mound, measuring 12 metres across at its summit and widening to 28 metres at its base, with characteristically steep sides. What makes this site particularly intriguing is the layered history visible in its structure; during the Second World War, military engineers constructed a concrete lookout post directly on top of the prehistoric cairn, partially levelling and removing some of the original monument in the process. At the base of the cairn’s southeastern side, you can still spot the remains of a small rectangular platform, likely built to support a flagstaff for the wartime tower.

The lookout post represents one of 83 identical structures erected around Ireland’s coastline between 1939 and 1942, part of the Marine and Coastwatching Service established to monitor and protect Irish neutrality during the war. Each post was assembled from 137 precast concrete blocks following a standardised design, creating a network of observation points staffed by soldiers working in pairs. These coastwatchers maintained constant vigilance, operating in eight or twelve hour shifts around the clock, with one man inside managing communications whilst his partner patrolled outside. Their duties included identifying and reporting all shipping and aircraft movements, as well as any suspicious communications or activity between vessels and the shore.

After the war ended in 1945, the Marine and Coastwatching Service was disbanded that October, and most posts were abandoned to the elements. Some found new life as marine communication stations, but many, like the one atop this cairn, remain as concrete reminders of Ireland’s wartime neutrality. The juxtaposition of the ancient burial mound and the 20th-century military structure creates a unique archaeological site where prehistoric and modern history quite literally stack upon one another, offering visitors a tangible connection to both the distant past and the more recent challenges of maintaining neutrality during a global conflict.