As we stood on the top of Oregon’s largest wilderness area, looking down upon mountains that spread across the horizon like rows of jagged teeth, we made a plan to celebrate by swimming in a lake partly covered by snow and ice. From the moment we’d entered the backcountry of the Wallowa Mountains it had been hot, and during the 3,400-foot gain in elevation to our campsite at Ice Lake – and the even steeper trek to the 9,826-foot summit of the Matterhorn that morning – we’d been marinating in a cocktail of sweat, sunscreen and bug dope.