A 100-mile backpacking trip is a good start for sizing up a wilderness area. The Spokane Mountaineers, celebrating their 100th anniversary this year, honored the centennial at the end of July 2015, with a week-long horseshoe-shaped route through Washington’s Pasayten Wilderness. ( Read story.) The area includes 531,539 acres hugging more than 50 miles of the U.S.-Canada border north of Winthrop. The plan called for hiking most of east-west Boundary Trail 533, which includes sections of the Pacific Crest (PCT) and Pacific Northwest (PNWT) national scenic trails. The Newby Lake fire closure prevented them from starting at Irongate Trailhead in the southeast portion of the wilderness and hiking the through the scenic Horseshoe Basin. So they started from Thirtymile Trailhead, picked up the Boundary Trail at Cathedral Lakes and headed west into incredible scenery mixed with drudgery in downfall prompted by 2006 wildfires. Relief came when they merged into the Pacific Crest Trail and headed south on the well-groomed scenic route to their shuttled vehicle at Harts Pass. Follow their trip in these photos by Outdoors editor Rich Landers.