Hadleigh Castle stands on high ground overlooking the Essex marshes, with origins dating to 1215 when it was built by Hubert de Burgh, a trusted advisor of King John. During the 14th century, King Edward III recognized its strategic importance defending the Thames estuary against French attacks and expanded it significantly, adding twin drum towers, a gateway, chapel, and living quarters. The major remains visible today include the distinctive pair of drum towers and barbican gate, constructed from Kentish ragstone cemented with mortar containing shells from nearby Canvey Island. One tower later served Georgian revenue men as a smuggler lookout. Though dismantled in the 16th century for building materials, the ruins remain a testament to medieval military architecture and royal ambition.
