If you stay on the Isle of Sheppey there are a few places of interest to visit. One is the war museum at Eastleigh between the prisons. Check the opening times as it is limited to a few days a week. It is very small but filled with information about the early pioneers of flying. The Wright brothers with Mr Rolls from Rolls-Royce built and flew the first planes from this island. It was a wonderful opportunity to learn and the volunteer was so knowledgeable and interesting to talk to as he gave us a personal tour and showed us all the photos etc. Well worth going to if you like a bit of history. Right beside this hut are a couple of other huts which sell bee products of beeswax and honey and hand made wooden items. Both of these are projects which the prisoners produce.
Also, the Abbey at Eastleigh which dates back to 600. Again there is a small museum with some lovely local volunteers willing to tell you some of the history of the island. You can also climb to the rooftop and on a clear day see right over to Essex and the North Kent mainland. The Abbey itself was also open and another knowledgeable volunteer was happy to tell us some interesting things about it.
Finally, the stoneware pottery place at Sheerness if you want any garden ornaments at really reasonable prices is worth a visit.