A completely overgrown graveyard sitting on the southern end of a low pasture ridge is not, on the face of it, an unusual thing to find in rural Kildare. What makes Killashee quietly remarkable is the density of history compressed into its roughly fifty by forty-five metres: finely carved eighteenth and nineteenth-century headstones, a handful of table tombs and slabs, the remains of two successive churches occupying the same ground, and, in the field immediately to the south-west, a souterrain, one of those underground stone-lined passages or chambers built in early medieval Ireland, whose function was likely a combination of storage and refuge.

The graveyard appears to sit on the site of an Early Christian foundation, suggesting continuous religious use of this ridge stretching back well over a thousand years. The church visible within the enclosure dates to the eighteenth century, but it was built on the footprint of an earlier medieval structure, and the western tower of that medieval building still stands. This layering is common enough in Irish ecclesiastical sites, where later communities simply rebuilt on ground that already carried spiritual weight, but it is relatively rare to have the physical evidence of each phase still present in a single, contained space. The whole site is registered as a historic monument.