The Battle of Roundway Down was fought on 13 July 1643, during the First English Civil War. A Royalist cavalry force under Lord Wilmot won a crushing victory over the Parliamentarians under Sir William Waller who were besieging Devizes in central Wiltshire, which was defended by Lord Hopton. Roundway Down and Oliver's Castle are about 1.5 km (0.93 mi) north of Devizes and now form part of the North Wessex Area of Outstanding Natural Beauty.