Double black (extreme) Big Sky, MT
Upper A-Z Chutes drops 565 vertical feet over feet of skiing, with a steepest pitch of 48°. That's steeper than 96% of the 2,251 double black runs we've measured in North America, and the 8th steepest of 290 named runs at Big Sky. It faces southeast.
Measured by ZRankings from 1-meter USGS lidar. Steepest pitch is the steepest stretch of about 50 vertical feet along the skiable line. Run lines come from OpenStreetMap and can sit a little off the skied path.