This landmark was the castle of John Sutter's domain, a walled compound with a variety of workrooms and living quarters built against the interior of the thick adobe brick wall. In the center of the spacious grounds stands Sutter's administration building, the only structure that is mostly original. The rest of the complex was in ruins in the 1890s, when restoration began in belated recognition of Sutter's many contributions to early California.Visitors explore the compound assisted by self-activated audio stations, which provide interpretive information on the history and activities of the fort. The materials and tools of daily life in Sutter's agricultural empire have been assembled in the various rooms and buildings of the compound, both as fixed exhibits and as material for living-history reenactments (inquire for schedule).