The Sommers Ranch Headquarters Historic District is a historic ranch complex located southwest of Pinedale, Wyoming. The district includes 11 wooden buildings, including a homestead house, a bunkhouse, a barn, and various other farm buildings and outbuildings. Albert P. "Prof" Sommers founded the ranch in 1908. Sommers married May McAlister in 1911; after the couple bought land from May's parents and her friend Nellie Yates, their ranch grew to 1,900 acres (770 ha).