Altamont is an unincorporated community in Alameda County, California. It is located 7.5 miles northeast of Livermore, at an elevation of 741 feet in the Altamont Pass. It was in 1969 the site of the Altamo…Altamont is an unincorporated community in Alameda County, California. It is located 7.5 miles northeast of Livermore, at an elevation of 741 feet in the Altamont Pass. It was in 1969 the site of the Altamont Free Concert at the Altamont Speedway. Originally called The Summit, the name was changed to Altamont when the Central Pacific Railroad arrived in 1869.