When I was young and silly, my parents used to take me to southern Utah to visit relatives almost every summer. We would spend a week or two in Kanab and I would devote hours each day to roaming the red hills and canyons in the area with my cousins. One of the activities in which we sometimes engaged was rock rolling. We would climb the K-hill, a small table-top mountain northeast of town and roll rocks down the side. It was awesome to see the largest boulders we could move crashing down the hillside, gathering momentum and speed, dislodging other great rocks and debris which joined the mad cascade to the bottom. There were times when it seemed as if the whole mountain was moving.
