This beach is popular with both locals and residents of neighboring cities, which gives it an in-your-own-backyard feeling—but it's not your backyard, so keep that top on.

The clean, 2.1-mile stretch of Manhattan Beach boasts more than 150 volleyball courts to practice used by amateurs and pros alike. El Porto, a popular surf spot at the north end of the beach, is the best place to catch waves. But wait your turn, dude! The locals can be fiercer than the waves if you drop in on their ride. The mellower boogie boarders claim the north side of the pier as their own. Lifeguards work year-round. On more solid ground, the South Bay Bike Trail is usually packed with bikers and inline skaters, especially on weekends. Joggers and walkers stick to The Strand, a paved walkway near the bike trail. Forgot your suit? No worries, there are two bathing-suit stores nearby.—Sarah Spada