The island sits at the mouth of Loch Erisort on the east coast of Lewis. It is small, rising to forty-three meters at its northeastern shoulder, with two lochans hidden in the centre that catch the sky on calm days. At high tide the channel between the island and Crobeag on the mainland fills with seawater and Eilean Chaluim Chille becomes a true island, cut off until the tide drops again. The causeway is rough underfoot and slick with weed; islanders have always known to read the tide tables before crossing. Get the timing wrong and you wait.

At the southern end of the island lie the ruins of Teampall Chaluim Chille, Saint Columba's Church. The walls are stubs now, low and lichen-covered, but the foundations trace out a building that served as the main place of worship for the entire parish of Lochs by the time it was mentioned in a report of 1549. There was probably a church here from the medieval period and very possibly earlier. The cemetery around it remained in use until 1878, which means that for at least four centuries the dead of half this coastline were rowed across the channel to be buried within sight of the open sea. Historic Environment Scotland now protects the site as a scheduled monument.

The chapel ruins are quiet now. Sheep graze among them. Skylarks rise from the rough grass and sing themselves invisible against the brightness. The wind off Loch Erisort moves through grass that has not been disturbed in centuries except by hooves and weather. The Columban monks, if they came, would have rowed up the loch in skin boats and pulled them onto a beach that has not changed shape in any way they would not recognize. The chapel they or their successors built grew and was rebuilt and finally was abandoned, and what remains is a low rectangle of stone on a small island that empties of people at every high tide and fills with birdsong at every dawn. For the parish of Lochs, this was the centre of life and death for a thousand years.