We took a cross-country route from Whitefish/Kalispell to Missoula, Montana, then over to Wala Wala, Washington by following Interstate 93 to Interstate US Hwy 12. I-12 is 99 miles of a winding road, but very scenic following the wide Clearwater River, with many rapids and great scenery. During this trip, you travel thru 3 states: Montana, Idaho and Washington within a 4-hour period!
The Clearwater River is in 74 miles flowing from the mountains of the Idaho-Montana border, following US Hwy 12, offering fantastic river rafting and fly fishing(mainly salmon and steelhead). Clearwater joins the Snake River at Lewiston and is the largest tributary of the Snake. The Snake River is over 1,000 miles long and is the biggest tributary of the Columbia River(the largest river in the Pacific NW).
The Lewis and Clark National Historical Trail also follows the river from Greer, Idaho to the confluence with the Snake River. In addition, the Northwest Passage Scenic Byway follows the Clearwater River from Grangeville, Idaho downriver to Lewiston, Idaho.