5. Descanso Beach
If this boozy, party-hardy beach was in LA proper, it'd be #1 with a bullet. Instead, it's a hidden treasure at #5, 'cause you've got to take a boat to get to it. But once you're there (after an hour or so of pre-party on the Catalina Express on the way over), you've got everything from volleyball courts to private cabanas, plus a 360-degree bar and grills set up for nighttime do-it-yourself steak-offs.