During World War II, Douglas had the main prisoner-of-war camp in Wyoming. The camp covered more than a square mile with 180 buildings, and from spring 1943 to winter 1946 it held up to 2,000 Italian and 3,000 German prisoners along with about 500 Army personnel. At that time it was larger than the town itself. The Officers' Club is the only building left standing, and it is now a state historic site. It is open seasonally, June through August, and the 2026 season has ended. From September through May, tours can be arranged by calling at least two days ahead. Staff are limited in the off season.