The National Historical Park administers Concepción, San José, San Juan Capistrano and Espada — the four Spanish colonial missions strung along the river south of downtown — along with the Espada Aqueduct and the Rancho de las Cabras. All of it is free. The main visitor centre is at Mission San José and is the right place to start: it carries the film, the context and the passport stamp, and the missions make far more sense in sequence than as separate stops. All four remain active Catholic parishes, which is the thing most visitors do not expect.