Two Rivers: Duchesne and Bear
I spent much of the last week going up one river and then down the other. I'd never heard of either one before, but since they're worth a week's touring, they're worth a mention.
The Duchesne River runs into the Green right where I met the Green at Ouray, Utah. I followed it up, up, and up through Fort Duchesne, Roosevelt, Duchesne, Tabioma, and right up to Wolf Creek Pass. Then I crossed over the top of the mountain there to the Provo River watershed and crossed up over another pass, but when I came out of the Uinta mountains, it was following the Bear River downn, down, down. Down to Evanston, down to Bear Lake, which straddles Utah and Idaho, and finally down all the way to Montpelier and Soda Springs, Idaho, where it finally veers to the south, to flow into the Great Salt Lake. (That's a 700-mile journey to get 90 miles from its headwaters!)
The Bear River part (downhill) has been pretty nice. The Duchesne and Provo River parts were pretty tough!