In the Bronze Age there were around 80 round houses at South Barrule
Two centuries of hidden Manx history have been revealed in a new documentary by the Manx Heritage Foundation.
The Castles and Forts of the Isle of Man examines the importance of over 45 lesser known historical Manx sites.
Aerial photography gives a picture of island life, from pirate invasions to the story of Manx hero Illiam Dhone.
Producer Charles Guard said: "It seems that the Isle of Man was one of the most heavily fortified bits of land in the whole of the British Isles."
He added: "People will immediately think of Peel Castle and Castle Rushen but places like the summit of South Barrule are less well known.
"In the Bronze Age there was a huddle of nearly 80 round houses there encircled by a stone rampart that would have defied any attempts at attack."
More details about the Castles and Forts of the Isle of Man can be found on the
Manx Heritage Foundation website