Blue Keystone, CO
Ptarmigan drops 591 vertical feet over 2,269 feet of skiing, with a steepest pitch of 20° about 920 feet below the top. That's steeper than 39% of the 5,615 blue runs we've measured in North America, and the 113th steepest of 140 named runs at Keystone. It faces northwest.
Facing northwest at an average 15°, Ptarmigan gets about 81% of the winter sun that flat ground at Keystone does, December through March. That's shadier than 53% of the runs we've measured, and the 75th shadiest named run at Keystone. Its top sits at 11,930 feet.
It gets an ordinary dose of sun: powder lasts a typical amount of time, and spring snow softens on a normal schedule. Shading from ridges and trees isn't counted yet.
under 25°25–35°35–45°45°+ Hover to follow the line on the map.
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.