The whole island of Vis was a military base for about 45 years and remnants of the army's presence can still be seen everywhere. The island was closed for visitors until late 1970s although the locals were allowed to travel off and on. Foreign tourists were not allowed to set foot on the island until the late 1980s.
The amazing thing is that when Croatia (along with Slovenia) proclaimed independence and the war in the former Yugoslavia broke out the army left the island without a single shot fired. They did leave behind a few mine fields, though, and although most mines were subsequently removed, one cost a reckless Dutch tourist his foot a few years ago.