Capt'n I think your going to need a few spare SD card's with you with all the potential clicking away going on. The Esplanade along Rochester Castle grounds & in front of the Cathedral might make a worthy back drop to a line up of XT's.

If you don't get your nautical fill at the Dockyard the I see the the rusty old wreck The Medway Queen that was, has had a major face lift and is moored up 5 minutes away. She was a big part of the 'Little Ships' evacuation from Dunkirk.

http://www.medwayqueen.co.uk

HMS Montgomery may still be laying in the Medway's estuary, that can be seen from the Strand when the tides out heavily laden with WW2 ammunition.