Few mountain-bike trails start off easy, but the South St. Vrain Figure 8 begins with six miles of sufferfest, much of it a rough alpine ride through boulder gardens, loose rocks, ruts and roots that finally eases into nearly four miles of easy road and mellow singletrack before returning to the abuse for another six. The elevation gain is a not-trifling 2,116 feet, making for a great early-season technical training ride; this is also a popular fat-bike ride, with some of the ground gnar covered in snow. The full Figure 8 includes Sourdough Loop, Little Raven, Waldrop and the Brainard Lake Cutoff, all of which adds up to nearly sixteen miles of magnificent misery.