Fast, Fun and Narrow. A brief, wonderful and definitely chilly canyon involving a few rappels and a long swim, Keyhole is a good introduction to technical canyoneering and a delightful way to spend an hour or two on a hot summer day. It is often combined with Pine Creek - no need to strip off the wetsuit and harness in-between.
This canyon was originally known as Starfish Canyon, as on the topo map, it has legs running in several directions. The first descent was by Ken Gronseth and Dennis Turville on August 10th, 1979. In the late 1990's its name morphed into Keyhole Canyon, and it became popular as an easy, fun outing. An arch can be seen far above the canyon from the parking spot. Is this the Keyhole?
Bring minimal gear. It's not unusual to put on wetsuits and harnesses at the car and dash up the approach as fast as possible, dropping into the cool of the canyon before succumbing to heatstroke.