Overlooking the Orwell Estuary, Landguard Fort is a site of extreme historic significance. It was originally built by order of King Henry the Eighth in the 16th century to guard the entrance to Harwich harbour, and is the last fort in England to have successfully opposed an invasion attempt in 1667, led by a significantly larger Dutch force. The current fort is a hybrid structure, largely constructed in the 18th and 19th centuries, with later additional Victorian installations. In collaboration with English Heritage, the Landguard Fort Trust run an ongoing programme of educational and display materials within the Fort.