Britain's Maunsell Sea Forts [wiki] were built during WWII as part of the coastal defense system. They were decommissioned in the 1950's, but many of them remain in use for non-military purposes (this is arguably the most famous). Some great photos here. [previously on metafilter]
Cats in Wartime on land, at sea, and memorialized. (With discussion of some of the most famous-- like Simon and Oscar.) Also, What Cats Know About War, previously on metafilter. [more inside]
ukgraves.info has thousands of photographs of cemeteries and gravestones all over the UK, from City of London to the Kirk of Lammermuir, and random points in between.