Starting outside Boise, this 150-mile loop rises from arid sagebrush desert to cool pine forests. It links three scenic byways, snaking past quiet towns, herds of elk, and some of the best white-water rafting spots in the West.
- IDAHO CITY This town of 500 was once the Northwest's most populous city. Step back 150 years with a visit to the Boise Basin Museum, which houses a collection of rare bottles plucked from area trash heaps. (208) 392-4550.
- KIRKHAM HOT SPRINGS After a four-mile detour east of Lowman on Highway 21, stop to soak in hot springs along the Payette River's south fork. It's a two-minute walk from Kirkham Campground. www.idahohotsprings.com .
- BANKS The north and south forks of the Payette merge right at the Banks Store and Café. Grab a strong cup of joe before heading south on Highway 55 through the river's gorgeous canyon. (208) 793-2617.
- THUNDER MOUNTAIN LINE At the town of Horseshoe Bend, hop aboard a classic Western locomotive with open-air train cars for a tour through secluded sections of the canyon. (877) 432-7245.
- EAGLE ISLAND STATE PARK Stretch your legs at this grassy 545-acre day-use park four miles west of Highway 55. If exploring the network of equestrian and hiking trails heats you up, cool off with a few trips down the park's waterslide. (208) 939-0696, www.idahoparks.org/parks/eagleisland.aspx .
- BOISE From Highway 55, take State Street into the city's vibrant downtown. Eighth Street brims with topnotch eats. Local favorite: the osso buco–style smoked boar shank at Gino's Italian Restaurant. (208-331-3771).
Illustration by Michael Klein 
This article was first published in May 2008. Some facts may have aged gracelessly. Please call ahead to verify information.