Lochlannach is an Irish term historically applied to Norsemen or Scandinavians, and while the name alone cannot tell us anything firm about who built or occupied the site, it suggests that local memory attached something foreign or out of the ordinary to this particular enclosure long before it was mapped or measured.

The antiquarian Thomas Johnson Westropp noted the name in 1901, and the cashel itself appears on both the Ordnance Survey 25-inch plan of 1897 and the 1920 edition of the six-inch map, though the structure is considerably older than either record. It sits at the eastern edge of a broad hill summit in rough pasture over karst limestone, the pitted, fissured rock characteristic of the Burren landscape, with open views running north to south. The cashel is subrectangular rather than the more typical circular form, measuring roughly 20.65 metres east-northeast to west-southwest and 18.1 metres north-northwest to south-southeast. Its double-faced stone wall survives well enough that the outer face can be traced almost entirely around the perimeter, with only a short gap of around five metres at the southwest. A portion of the outer face at the north-northwest to east has been rebuilt to a height of two metres. The entrance, just under a metre wide, faces southeast. Inside the northern part of the enclosure there is a souterrain, an underground stone-lined passage or chamber that in early medieval Ireland was typically used for storage or concealment. A small cavity near the southeastern entrance may be the remnant of a stone-lined drain. Outside the western wall, later additions are visible: two rectangular structures and a narrow stone-built terrace that tapers as it runs northward.

What gives Caherlochlannach additional weight is its context within a wider landscape. Research published by Bowmer in 2019 identified it as part of an integrated complex, connected within a shared field system to a nearby enclosure roughly 38 metres to the southwest and another cashel approximately 229 metres to the west-southwest. A cairn, a mound of stones that may mark a burial or boundary, lies about 93 metres to the west. Together these features suggest not an isolated farmstead but a coordinated, multiperiod use of this hilltop, with different structures from different eras layered across the same ground.