San Francisco, California
Ocean Beach, San Francisco, is an awesome 4 mile long stretch of beach located on the west side of town and is named ocean beach because it faces the Pacific Ocean, not the San Francisco Bay. These pictures don't do it justice, at least click on them to get a full size picture. The beach is partly across the street of the west end of Golden Gate Park and close to the San Francisco Zoo. To get to Ocean Beach, just work your way west through town. It is important to note that Ocean Beach is not a beach you can go in the water. If you want to go swimming, head to a beach on the bay, or north to Stinson beach, or south down the peninsula to any number of beaches.
The beach is free to visit and you're largely left on your own to come up with something to do. If the surf is up, you can watch the surfers. There are three parking lots near Ocean Beach. Going further south increases your chances of finding a parking spot.
Walk north and you will eventually get some great views of the Golden Gate Bridge as well as the properly named "Seal Rocks" where sea lions hang out.
Overall, Ocean Beach is a great place to go (you can even bring your dog) on a sunny day and even though you're only minutes away from millions of people you can still enjoy a quiet space of beach. If you do go on a cloudy day, just make sure you dress warm- and depending on how adventurous you are, you might want to take a change of clothes. Night is also a good time to visit as you can build a bonfire and stargaze.