On a cold, drizzly day in July 2026, Nate Lewand and his fleet of whitewater rafters passed by Black Canyon, an obsidian-colored gorge on the Main Salmon River in Idaho. As they rounded the bend, they spotted a woman standing on a narrow sandy beach far too small to hold a tent. She wore clean linen clothing, military-style boots, and carried a burled walking stick. Despite being right at the water’s edge in the rain, the woman was bone dry. She had no gear—no ropes, no backpacks, and no raft. “She was just standing there,” Lewand told Outside. “We hollered...