In an otherwise arid stretch of the American Southwest is a seemingly bottomless, deep blue swimming hole that has built up quite a reputation.

Local legend has it that outlaw Billy the Kid would take a dip in the Blue Hole before heading into Santa Rosa. Weary railroad workers and passengers followed at the turn of the century, and then came the flood of travelers along historic Route 66.

The artesian spring, tucked into a rock outcropping just off the highway, pumps out some 11,000 liters of water per minute. That's enough to fill a standard swimming pool in short order, so it's no wonder that the steady flow results in crystal-clear conditions that have attracted divers from around the world.