A number of governments maintain permanent research stations in Antarctica and these bases are widely distributed. Unlike the drifting ice stations set up in the Arctic, the research stations of the Antarctic are constructed either on rock or on ice that is (for practical purposes) fixed in place.
Many of the stations are staffed around the year. A total of 40 countries (as of October 2006), all signatories to the Antarctic Treaty, operate seasonal (summer) and year-round research stations on the continent. The population of people performing and supporting scientific research on the continent and nearby islands varies from approximately 4,000 during the summer season to 1,000 during winter (June). In addition to these permanent stations, approximately 30 field camps are established each summer to support specific projects