I believe this is Fort Barrington on the south side of St. John's Harbor. The early morning mist obscures the picture. Good information on these forts and English Harbor can be found at http://nationalparksantigua.com/
Fort James Guarding the Northern Arm of harbor at St. John this for is open but I was unable to visit.
I have found no name for this fort in the inner harbor of St John Antigua clearly this for wast to provided shore defense for the town and to protect the inner harbor.
On the other side of the island is English Harbor Antigua Home of Nelson Dockyard. This was one of the Royal Navy's main basses in the Caribbean.
A Major fortification, fort Berkeley home to a battery of 25 heavy Cannons. A boom of tree trunks and Chain would stretch across the harbor entrance to project the fleet. In the Foreground is the what I believe is the Yacht club, which was once a the Royal Navy Dockyard.
Not a fort but a Sugar Factory (latter Cotton) on Tortola. Until the 20th Century this location was on the waterfront. Now its a free museum located well in land with a lot of farming and industrial hardware and items salvaged from ship wrecks. Well worth the 45 minutes to an hour it takes to look around in. I'll probably add interior pictures at some point. For more images and information see: http://www.bvi.org.uk/islands/museums and http://www.bvi.org.uk/files/sugarworks.pdf