Onsight Rock Gym, Knoxville

Onsight Rock Gym isn't just another gym with a rock-climbing wall or two. It's a dedicated rock-climbing facility with more than 12,000 square feet of climbing walls that stretch more than 50 feet up, offering classes, clubs, teams and programming for all ages and abilities.

The gym is the brainchild of Christian Robinson and Yoli Chen, rock climbers who met while scrambling up crags in Southern California. They partnered with leading climbing-wall producer Walltopia to produce a facility to appeal to both beginner and hard-core climbers.

Onsight's acid green, gray, and white walls jut out at diverse angles and feature color-coded stones that designate routes for different experience levels. The facility also welcomes boulderers, who climb steep walls without the help of a harness or giant roll of duct tape. Onsight has a few non-climbing options, too, including yoga and floor-based fitness.