There is something magical about river sources. British Columbia’s Fraser begins in a shallow pond, on a pass amidst the soaring Canadian Rockies. Idaho’s Selway emerges crystal clear and cold, surrounded by green sedges and wildflowers. The source of the Green River sits high in Wyoming’s Wind River Range, near Knapsack Col. It is stunningly beautiful.

Joel Griffith of Salmon, Idaho, trekked with me for three days to reach the source. We then followed the water downstream until it was deep enough to launch our pack rafts. That was at a place called Three Forks Park, where the water of Wells Creek boosts the flow.

There was whitewater. There were logs.

On our second day of floating, we passed Flattop Mountain. You know it, it’s on the Wyoming license plate.

Our Green source descent finished where many Green River headwater trips begin, at the outlet of Green River Lakes. This is where Buzz Holmstrom started in 1937, taking his wooden boat all the way through the depths of Grand Canyon—a spectacular journey.