La Brea Tar Pits, Los Angeles.

If you've seen the film "Volcano", these are the tar pits that the volcano popped up out of, on Wilshire Blvd. Apparently back after the last ice age, a whole load of big animals (mammoths, sabre-tooth tigers, giant sloths etc) fell in and got trapped in the tar here and their bones were preserved. This is LA's claim to having some ancient history, I suppose.