Yep; this is the scene at "Footstock", the gathering in the Polo Field at the end of a Bay to Breakers race.

The B2B is an annual 12K held in San Francisco in May. Generally fields 75,000 or so walkers, runners, streakers and Elvis impersonators. There's a costume contest held along the way, and a good time is had by all (or most).

Some of the more "only in SF" aspects of this:

1) The crowd at the start is so large that by the time the last folk reach the starting line, the winners have already finished (and generally are Kenyans).

2) "Centipedes". A group of runners roped together. Some are competitive, some are just for fun. There is a prize for the first centipede to cross the finish line. For years UC Davis students/alumns sponsered a centipede which prided itself on beating the first female finisher. At long last that streak was broken. There are specific rules as to how many runners and how lashed togther they have to be. Traditionally, the first runner in a 'pede wears a set of antennae.

3) Nude runners. Not officially sanctioned, but rarely arrested.

4) The Salmon. A group of runners dressed as salmon, who run the race from finish to start (as in salmon swimming upstream). I usually hit them somewhere around mile two. Considering this is a 7.5 mile race, you can see how slow I am.

5) The costumes. Anything and everything. Some topical, others just plain weird. Always a group of Elvis impersonators in a group. Dumbest thing I ever saw was a guy dressed as an alligator, stomach down on a skateboard trying to push himself the entire 12K. People kept stepping on/tripping over him.

6) Booze on wheels. Being cracked down on, but on the course there have been things such as an entire rolling Tiki bar, to frat boys pushing kegs of beer in a shopping carts.

Footstock has food, beer (although much more controlled than a decade ago; you're fenced into a small compound now), and about a gazillion porta-potties. There usually is a band or bands.

I've missed the last several races.

As for the other one; right state, wrong location.

I'll give you what may be a misleading clue: that bright thing in the picture is not the light, it's the SETTING sun. So I'm standing roughly East of the lighthouse, on the beach, with the water at my back.