Peace camps are a form of physical protest camp that is focused on anti-war and anti-nuclear activity. They are set up outside military bases by members of the peace movement who oppose either the existence of the military bases themselves, the armaments held there, or the politics of those who control the bases. They began in the 1920s and became prominent in 1982 due to the worldwide publicity generated by the Greenham Common Women's Peace Camp. They were particularly a phenomenon of the United Kingdom in the 1980s where they were associated with sentiment against American imperialism but Peace Camps have existed at other times and places since the 1920s.