Hearst was elected to the California State Assembly in 1864, serving one term from 1865 until 1866. He was one of 12 members representing San Francisco. His knowledge of mines and the mining industry proved valuable, and he was selected for a special Committee on Mines and Mining Interests. During this time (1865) he acquired Rancho Piedra Blanca at San Simeon, California. He later bought parts of adjoining ranchos. This land was later developed by his son as the Hearst Castle. The Hearsts also maintained a townhome in San Francisco at the corner of Chestnut and Leavenworth.