If you’re a thrill seeker, the Greater Farallones National Marine Sanctuary, about 30 miles west of San Francisco, is home to some of the world’s largest great white sharks and northern elephant seals. You can choose a charter boat dive or a great white shark dive adventure in a cage for about $825/diver or $475 for topside observers. Not a diver? About 300,000 birds nest here annually, as well as harbor and elephant seals, California and Steller sea lions, northern fur seals, four types of whales (blue, grey, humpback and orcas), dolphins, and porpoises. sharkdiveadventures.com