Following the Russian invasion of Finland in 1939, the U.S. Army began construction of a training outpost to be called the West Yellowstone Winter Training Camp near Henrys Lake Station. Plans were created that included a 100,000 acre training area that could hold 30,000 personnel. Some buildings were constructed in 1941, but were ordered destroyed in 1942. At the time, the military offered no reasoning for the reversal of the plan. It was later discovered by an Ashton resident that the military did not want to interfere with trumpeter swans which used the lake as a breeding ground. The winter training program was relocated to Fort Drum in New York.