Chatham BarrierChatham, UK
The Chatham Barrier is a dry ditch protecting the southern approach to the dockyard. It runs down from Upper Cornwallis Battery in Fort Amherst, to Chatham Reach by the old Ordnance Yard. The casemated guns, covering the Reach, have recently been uncovered at the foot of Ditch.
The Great Lines or Chatham Lines were built along a ridge line that ran from the North to the South just inland from the Chatham Dockyard. Work started on the Lines in 1756 and continued through to 1815. This includes the Lower Lines built to the north as the Dockyard was expanded. Thereafter only minor changes and improvement were made to the Great Lines.
The Barrier Ditch is dominated by the defences in Fort Amherst.