Caldey Lighthouse was built in 1829, by Trinity House, the lighthouse authority for England and Wales. It works in conjunction with Lundy North Lighthouse to aid navigation in the northen Bristol Channel.
The lighthouse was originally powered by oil and required resident keepers to keep it in operation. In 1927 it was converted to an automatic acetylene system, after which the station was only being looked after by a part-time attendant. In 1997 the lighthouse was fully modernised and converted to mains electricity.