Ocean Beach, at the end of Golden Gate Park, on the westernmost side of the city, is San Francisco's largest beach -- 4 miles long. Just offshore, at the northern end of the beach, in front of Cliff House, are the jagged Seal Rocks, inhabited by various shorebirds and a large colony of barking sea lions (bring binoculars for a close-up view). To the left, Kelly's Cove is one of the more challenging surf spots in town. Ocean Beach is ideal for strolling or sunning, but don't swim here -- tides are tricky, and each year bathers drown in the rough surf.