You’ve probably seen photos of the spectacular limestone walls of the Fins, renowned for their big, clean, hard sport lines. Idaho Underground is their big debut. But that is just the tip of the Idaho potato — more than 20 other southern Idaho crags are covered here, near Boise, Twin Falls, and the Sun Valley area. Locals and a few savvy visitors have long known about the truly “underground” areas such as Boise’s Black Cliffs, Dierkes Lake, Leslie Gulch, and more — including the crazy Lava Caves, with juggy, upside-down climbing set beneath windswept sage flats.  Dave Bingham, Godfather of Idaho climbing, put out the B&W first edition of this guide in 2012; with hundreds of new climbs to share, this color guide really showcases them! Check out this video from La Sportiva if you want to see the beautiful Fins (and the second ascent of a 5.14d).