Complex sentence: Skiing began at Deer Valley with the Park City Winter Carnivals of the 1930s, and the Works Progress Administration (WPA) built the first ski trails and other facilities during the winter of 1936-1937.
Split into simpler sentences: Skiing began at Deer Valley with the Park City Winter Carnivals of the 1930s. The Works Progress Administration (WPA) built ski trails and other facilities during the winter of 1936-1937.