Border To Border


The only substantial town for 50 miles in any direction, Challis is an old mining camp that has grown into a miniature version of Salmon—albeit without the water or the tourists. Apart from boasting the all-time Idaho record for least rain in a year (seven inches), Challis is a quiet market center for local cattle ranchers, with more bars—and barber shops—than you’d expect of a town this small.

On the south side of Challis, at the junction of US-93 and Hwy-75, the excellent, modern Land of Yankee Fork State Park visitors center (208/879-5244, daily summer, Wed.-Sat. fall-spring) has extensive displays on local mining history and maps to guide visitors to many evocative ghost towns and other relics sprinkling the surrounding hills. Gold was first discovered in the region in the 1870s, and nearby mines and mining camps boomed for the next 25 years, though by 1905 the last mine had closed. A few gold mines have reopened in recent years, though all of these are hidden away in isolated areas and protected behind high-security walls and fences; none are open to the public.

The Lost River Valley

At Challis, our main route follows the 1940s alignment of US-93, heading west into the Sawtooth Mountains, but today’s US-93 swings southeast toward Arco and the Craters of the Moon National Monument and Preserve through the Lost River Valley. The scenery here remains spectacular, with the mountains towering over the ranches of the valley floor, but it can’t compare with the glories of the old road route.

But if you’re in a rush, or there’s been a recent storm blocking the mountain passes, or you just want to see another corner of Idaho, US-93 will be there for you. Mountaineers follow US-93 on their way to climb 12,662-foot Mt. Borah, the highest point in Idaho and a demanding though not technically difficult summit to reach. A popular trailhead is at the end of the well-signed Borah Peak Access Road, roughly halfway between Challis and Mackay. For details, contact the U.S. Forest Service ranger station (208/588-3400) in Mackay.


The rough-and-ready town of Mackay (pop. 487; rhymes with “wacky”) is the valley’s hub. You can stay at the Wagon Wheel (809 W. Custer St., 208/588-3331), where rooms with kitchenettes go for as little as $45. Mackay also hosts an annual rodeo and the Custer County Fair, but it’s best known for its famous free barbecue on the third Saturday in September, when hundreds of people come here for general fun and games and massive amounts of free food (Tons of Meat—Mackay’s Treat, say the signs).

South of Mackay, US-93 continues to Arco, then elbows west through the eerie Craters of the Moon, rejoining Hwy-75 at Shoshone.

Related Travel Guides

Map of the Border to Border Route through Idaho

Map of Border to Border route through Idaho.
Map of Border to Border route through Idaho.