#814515. Immaculate Conception Church - Old Town San Diego Historic Catholic church in the heart of Old Town San Diego, California. On July 22, 1917 Immaculate Conception Church was opened for divine worship. The Solemn Dedication took place on July 16, 1919 at the hands of Right Reverend John C. Cantwell, D.D., Bishop of Los Angeles and San Diego. Ic-sandiego.org~Site InfoWhoisTrace RouteRBL Check