What sets Leacanabuaile, or Leaca na Buaile as it is known locally, apart is the sheer density of life compressed within its roughly 23-metre diameter. Six houses, a drainage system, a hidden underground passage, and incised carvings of uncertain age are all packed inside a single drystone wall, the whole ensemble sitting within a group of three such cahers positioned between the Valencia estuary and Cooncrome Harbour.

Excavations carried out in 1939 and 1940, reported by Ó Ríordáin and Foy in 1941, revealed that what had appeared to be a sod-covered bank was in fact the collapsed remains of a substantial caher wall, a term used for a stone-built ringfort, averaging 3.3 metres wide at the base and incorporating two internal chambers and a series of terraces accessed by steps of projecting slabs at ten points around the circuit. Beneath the rubble lay the foundations of six stone houses, three circular and three rectangular, the circular ones predating the rectangular, with the largest rectangular house actually built over the ruins of two earlier circular structures. The excavators proposed a ninth to tenth-century date for the site's construction and use, a period reflected in the finds: iron knives, a sickle, a ploughsock, bone comb fragments, rotary quern fragments, and a bronze ring-headed pin. The animal bones tell their own story, cattle dominating the assemblage but joined by sheep, pig, deer, grey seal, fish, and sea-birds, suggesting a community with access to both farmland and the sea nearby.

The most quietly extraordinary feature is the souterrain, an underground stone-built passage of the kind used in early medieval Ireland for storage or refuge, which runs from the interior of the best-preserved circular house, beneath its wall, through a low creepway fitted with a neatly cut arch stone, and into a chamber built within the caher wall itself. The first passage, just 0.8 metres wide and 0.75 metres high, curves gently downward over 6.2 metres before connecting to a second passage aligned east to west. On the north wall of this first passage, close to the creepway, are incised carvings including concentric circles and a quadruped animal; whether they were cut into bedrock or merely into a layer of dried mud that coats it remains uncertain. The site was conserved and restored following the excavation, and a low opening was later built through the caher wall's external face to allow access to the overhead wall chamber, giving visitors a rare chance to move through the same layered spaces its ninth-century inhabitants would have known.