A big barn of a place, the city’s largest indoor climbing gym has 35-foot-high ceilings, walls that suggest some stiff challenges—the Pinnacle, Pyramid, H, the Roof—and routes (several hundred of them) that wind their way out of caves, up overhangs, and across roofs, while challenging climbers with various textures and styles of climbing. Both top-roping and lead routes are available and clearly marked, as is the degree of difficulty. Beginners take a mandatory introductory lesson ($35, admission and rental included). Experienced climbers have to demonstrate their safety savvy and belaying skills. Advanced and intermediate courses are also available. A climbing cave with a well-padded floor is popular with kids and their birthday planners.