Arthur S. Heineman was the inventor and primary architect of the world's first motel, the Motel Inn. It was originally called the Milestone Mo-Tel and is located in San Luis Obispo, California. It opened on December 12, 1925. Although it was planned to be only the first of a chain of eighteen motor courts, Heineman was unable to register the name as a trademark, which allowed competitors to use the name, and his plans to extend the concept himself were scuttled.