Red Rocks

I don't know of any open-air theater that is more spectacular than Red Rocks Amphitheater, outside of Golden, Colorado.

The theater was literally carved out of an outcropping of red rocks between 1936 and 1941. It sits at 6,450 ft above sea level, can seat 9,450 spectators, and is a geological phenom: the only naturally occurring, acoustically perfect amphitheater in the world. You can hear unaided voices from every seat in the theater. Artists as varied as Sting, the Beatles, U2 and opera stars have performed there.

The best thing though is sitting there at night, listening to whomever is performing, against the backdrop of a star-filled sky. I caught my very first concert in the US there, some 30 years ago and couldn't resist visiting again as we drove past :))

Here are some other shots of the place.