San Diego Haunted Photo gallery Mission Basilica San Diego de Alcala. Located at 10818 San Diego Mission Rd, San Diego, CA 92108, Mission Basilica San Diego de Alcalá was the first Franciscan mission in The Californias, a province of New Spain. Located in present-day San Diego, California, it was founded on July 16, 1769, by Spanish friar Junípero Serra.