Castle Harbour is a large natural harbour in Bermuda. It is located between the northeastern end of the main island and St. David's Island. Originally called Southampton Port, it was renamed as a result of its heavy fortification in the early decades of the Seventeenth century.

St. David's Island is one of the main islands of the British Overseas Territory of Bermuda. It is located in the far north of the territory, one of the two similarly sized islands that make up the majority of St. George's Parish.