Alpine, more fully Alpine Springs and also called Harold, was an unincorporated community in Los Angeles County, California located 2 miles south of where Palmdale is now. The Trego Post Office was located at the Alpine Station stop on the Southern Pacific Railroad which stood at what is today the intersection of Sierra Highway and Barrel Springs R…Alpine, more fully Alpine Springs and also called Harold, was an unincorporated community in Los Angeles County, California located 2 miles south of where Palmdale is now. The Trego Post Office was located at the Alpine Station stop on the Southern Pacific Railroad which stood at what is today the intersection of Sierra Highway and Barrel Springs Road. The Trego post office was in operation from July 1, 1884, until December 18, 1884, when the name was changed to Harold. The first Harold post office was established on December 19, 1890, and was discontinued on September 16, 1894. A second post office named Harold was in operation from July 13, 1895, until June 15, 1901, when the papers were moved to Palmdale.