Lismore is famously associated with Saint Moluag. It was a major centre of Celtic Christianity, and the seat of a bishop. To modern eyes it seems an isolated location for such a centre, but in an era when the fastest and most reliable transport was by water, Lismore was ideally situated.
There are two ruined castles on the island.
The name Lismore comes from Gaelic and means "Great Garden". It reflects the fertility of a relatively low-lying island amidst mountainous surroundings.