Sidmouth ) is a small town on the English Channel coast in Devon, South West England. The town lies at the mouth of the River Sid in the East Devon district, 15 mi south east of Exeter. It has a population of about 15,000, of whom 40% are over 65. The town is a tourist resort and a gateway town on the Jurassic Coast World Heritage Site. A large part of the town has been designated as a conservation area.