About 4.5 miles inland from central Oceanside was the largest California mission and the most successful in recruiting Native American converts. At one point some 3000 neophytes lived and worked here. After the Mexican government secularized the missions, San Luis fell into ruin; the adobe walls of the church, from 1811, are the only original parts left. Inside are displays on work and life in the mission, with some original religious art and artifacts, plus a tranquil cemetery.
In the garden, look out for the oldest pepper tree in California, which was planted in 1830 by Father Antonio Peyri. There's a small coffee shop on site. Behind-the-Scenes Tours run at weekends, with lunch ($24, with reservation).
