In the angle of the boomerang, the sheltreed modern harbour at Church Bay is a useful staging post for yachts heading for he Hebrides. Rathlin boatmen are pleased to point out Sloughna-More, "the swallow of the sea", a whirlpool at the southern tip of Rathlin where St Columba is said to have narrowly escaped drowning on a voyage from Ireland to Iona in the sixth century.
The first recorded shipping disaster in Rathlin Sound was in about AD440 when Brecain, son of Niall of the Nine Hostages, and his fleet of fifty curraghs were lost in a great tide rip.