Martyn was born and bred in Bury St Edmunds. He was a committee member responsible for heritage and history for the Bury Society. On behalf of the Bury Society he was the co-ordinator of a blue plaque scheme for the town which was completed in 2012. This involved a lot of research including producing a pamphlet about the plaque recipients. On several occasions Martyn has liaised with the local press on various aspects of Bury St Edmunds. Over the years he has been involved with writing articles on the town's history and has contributed to four booklets produced by a local history group, Bury Heritage Guides. As an amateur historian he also gives talks on the history of the town.