From The Wonders of Ireland by Eric Newby and Diana Petry (New York: Stein and Day Publishers, 1970):

Leacanabuaile Fort

Two miles north-west of Cahirciveen at the southern end of the Iveragh Peninsula; north of the Valentia river, on a hillside, reached by a minor road to Cooncrome Harbour. Leacanabuaile ('Hillside of the Summer Pastorage') is a fine, partly-reconstructed stone fort on a massive rock foundation, its stone walls enclosing an almost circular area 70 feet in diameter. Protected on three sides by steep grassy slopes, the entrance is on the eastern side. The walls, mostly 10 feet thick and with irregular steps leading up on the inside, contain the remnants of a square dwelling house built on top of earlier circular ones; another clochan on the western side has a cavity leading to a long souterrain. Excavation produced Iron and Bronze Age objects, suggesting the existence of an early Christian farming community. From the top of the remparts there are fine views down to the coast, where the gaunt ruins of Ballycarbery Castle, a fortress of the MacCarthys, stand black against the skyline. At least two other similar, but lesser forts, and some standing stones, are in the district. (page 85)

From The Archaeology of Early Medieval Ireland by Nancy Edwards (Philadelphia: University of Pennsylvania Press, 1990):

House A at Leacanabuaile, Co. Kerry, is a good example of a round clochán from an excavated ring-fort site. It is situated against the wall on the far side of the enclosure, the doorway facing the entrance. The walls are up to 1.5m (5 ft) thick and they are corbelled from a height of 1.2m (4 ft). However, the roof does not seem to have been of solid stone. Five post-holes around the perimeter of the interior would tend to suggest that they supported a timber-framed roof possibly capped with thatch. An aperture in the floor near the entrance gave access to the souterrain. While House A was still standing, House B, a sub-rectangular structure measuring internally 7.1m (23 ft, 4 in) X 6.15m (20 ft, 2 in) was built abutting against it. The walls, which survived to a maximum of 1.5m (5 ft) high, are up to 1.83m (6 ft) thick and constructed to an excellent finish. Post-holes cut into the floor may indicate roof supports. A drain dug into the clay and covered with slabs runs from the doorway of the house to the ring-fort entrance.

It has been noted that in the case of Leacanabuaile the rectangular house is secondary to the round one. The same pattern has been recognized elsewhere and sufficient evidence has now accumulated to suggest that this is an important chronological marker. . . It is difficult at present to be precise about when the change from round to rectangular dwellings took place, but . . . a date in the eighth or ninth centuries seems likely. . . (page 26)

See also this scale plan of Leacanabuaile.