The majestic San Luis Rey church is the sole remaining cruciform mission church. During the mission period, a large outside hallway with 32 Roman arches spanned the front of the friary or convento. A perimeter fence allows access to the Mission quadrangle (now part of the retreat/conference complex). The first Mass said in California was celebrated here by Father Junipero Serra on September 16, 1771. The church was built between 1772 and 1776 by Spanish settlers at the site of what would later become Los Angeles. The original church building was constructed with stone obtained from the nearby hills. In 1812, after the Mexican War of Independence, Mexico gained control of California, and in 1821 the mission was transferred to the newly established Church of Rome. Pope Gregory XVI made the mission parish an abbey and named it Santa Maria della Merced. In 1834, during the secularization of Spain's missions, the abbey was given to the University of Notre Dame. The university closed the abbey down in 1845 because of financial difficulties and sold its buildings. In 1847, the town council of Los Angeles bought the abbey's land for use as a public park. The city government demolished most of the mission buildings over time to make way for streetcars and rail lines. Only the rectory, sacristy, and parts of the garden remain today. They are under protection of the City of Los Angeles as historic monuments.