DOTSERO, Colo. (AP) — At the base of Colorado's lone active volcano is a small mobile home park, where on this day a resident offers a fair warning to a pair of curious visitors.

"Is it four-wheel drive?" he asks. He bends down to scoop dark soil that crumbles in his hands. "We have a lot of this stuff, see?"

The stuff is left over from Dotsero's eruption, estimated to be 4,200 years ago. This was back when the Egyptian pyramids were being built. Back when native tribes roamed this land that appeared much like it does today, the mountains and streams stretching west to what is now called Glenw...