The ruin is dedicated to St Mac Dara, a sixth-century saint particularly venerated along this stretch of the Connemara coast, and the building retains enough stonework to suggest both its original proportions and the losses it has suffered over the centuries. Measuring roughly 13.4 metres in length and 7.3 metres in width, it is modest in scale but well-oriented along a WSW-ENE axis, as was common for medieval Irish parish churches.

The most telling detail is the doorway set into the south wall. On its inner face, a chamfered round-headed arch survives, complete with a hood-moulding, the projecting drip course designed to throw rainwater clear of the opening, finished with decorated terminals at either end. The outer face, however, was robbed of its dressed stone sometime before the early nineteenth century, a loss noted by O'Flanagan in 1927. This kind of selective quarrying was common across Ireland during periods when cut stone was more valuable than the ruins it came from. Elsewhere in the fabric, a lancet window remains in the east gable and a small chamfered window in the south wall, while the north wall preserves faint traces of what appears to have been a second doorway. One feature has vanished entirely: an altar known as Leac Síothnach, or Lackshinnagh Altar, which appeared on the Ordnance Survey six-inch map approximately 80 metres to the north-north-west of the church. No physical trace of it survives today, leaving only the placename as evidence that something of significance once stood there.