Fort Ruby, also known as Camp Ruby, was built in 1862, during the American Civil War, in the "wilderness of eastern Nevada." It protected the overland mail coaches and Pony Express, which linked California to the Union. It was operated 1862 to 1869. It was located at the east entrance to the Overland Pass from Ruby Valley, near Hobson on the west side of Ruby Lake. It was declared a National Historic Landmark in 1961.