Aztlan — David Wood

Maddock and Bones go rock climbing in a remote area of the American Southwest and stumble upon a place out of legend that changes their world.
 
*This short story originally appeared as a bonus story in The Dane Maddock Adventures Volume 1, and again in Primitive- A Bones Bonebrake Adventure. If you're a voracious Maddock reader, there's a good chance you already own it. It's being published separately at the request of many readers.