Jamesburg is an unincorporated community in Monterey County, California. It is located 7.5 miles northeast of Ventana Cone, at an elevation of 1722 feet. John James founded the town in 1867. The Jamesburgh post office opened in 1886, changed its name to Jamesburg in 1894, and closed for good in 1935. In 1968, COMSAT built the Jamesburg Earth Station- no longer operational- in the area.