The “River of No Return” in this pristine wilderness in central Idaho refers to the Salmon River, a famous whitewater rafting destination known for its powerful current. The name is just as well, given the truly rugged nature of this 2.3-million acre wilderness, the second largest in the lower 48 after Death Valley. Apart from a few airstrips, there are only a handful of service roads and 1.5 million acres without any trails at all. The Salmon River cuts a gorge deeper than the Grand Canyon in places, and the mountains are steep and nearly impassable, making them the perfect habitat for threatened species like gray wolves, mountain lions and wolverines. And if you want more solitude, “The Frank” is contiguous with another million acres of roadless Forest Service land, and separated from the 1.3-million acre Selway-Bitterroot Wilderness by a single dirt road.