Mission Beach. The HMCS Yukon, a decommissioned Canadian warship, was intentionally sunk off Mission Beach to create the main diving destination in San Diego. A mishap caused the ship to settle on its side, creating a surreal, M.C. Escher–esque diving environment. This is a technical dive and should be attempted only by experienced divers; even diving instructors have become disoriented inside the wreck, and a few have even died trying to explore it. Mission Beach, San Diego, CA.
San Diego–La Jolla Underwater Park Ecological Preserve. Diving enthusiasts the world over come to San Diego to snorkel and scuba dive off La Jolla at the underwater preserve. Because all sea life is protected here, this 533-acre preserve (all of La Jolla Cove to La Jolla Shores) is the best place to see large lobster, sea bass, and sculpin (scorpion fish), as well as numerous golden garibaldi damselfish, the state marine fish. It's common to see hundreds of beautiful (and harmless) leopard sharks schooling at the north end of the cove, near La Jolla Shores, especially in summer. La Jolla Shores and Ellen Browning Scripps Park, La Jolla, San Diego, CA, 92037.
Scripps Canyon. Off the south end of Black's Beach, the rim of Scripps Canyon lies in about 60 feet of water and comprises the Marine Life Refuge. The canyon plummets more than 900 feet in some sections. San Diego, CA, 92037.