Nomadic Mongolians became a horde because they knew how to survive, and you can bet the yurt played a part in their survival: A circular, portable tent that kept them warm while they hoofed it through the frigid wasteland, the yurt is now proving to be a popular alternative for winter campers in Colorado. Colorado State Parks now offers yurt accommodations -- skylighted, low-impact canvas tents wrapped around wooden frames and featuring wood-burning, gas or electric heat -- by reservation at State Forest and Ridgway state parks, for a reasonable fee (also coming soon to Pearl Lake, Mancos and Golden Gate state parks).