This battery on high ground in Portland, Dorset was built in the mid 1890s, but were obsolete by 1906. The site now looks in a sorry state, largely due to graffiti and litter.
Had a good look around there back in 2017. There are some very interesting places on the Isle of Portland.
Our B&B host (in Weymouth) says its very frustrating that Portland does not promote its self and that many business's and bus services seem to shut down outside of the main summer season. We had a great time there yesterday. The strong winds were whipping up the sea at Portland Bill, and the sculptures at Tout Quarry were amazing!
If you are brave the ditch of HMP Verne is impressive and appears to be publicly accessible. When I walked there the Prison Service opened up a sally port door in the ditch and we climbed into the prison itself, which was designed as a citadel. Interesting place, though many of the batteries were covered in brambles.