This is the Manhattan Beach pier. It's a wondrous thing watching the waves hit the pilings while surfers take a chance on navigating them.
What happened to this guy?
Further up a bit, on the sand part, people took advantage of the pier's cooling powers.
Wouldn't you know it, but there is an article on Wikipedia about this pier. It was built in 1901. You can learn more here: http://en.wikipedia.org/wiki/Manhattan_Beach_pier