Two rivers that flow north in the United States are the Teton and the Snake rivers in Idaho. When we think of rivers in the northern hemisphere, we assume they all flow south. It makes sense, to us south is down.
The lowest point in Idaho is the Snake River at 710 ft. This is right near the town of Lewiston. The Snake River in Idaho is made up of the Henry’s Fork and the South Fork of the Snake which meets up outside of Idaho Falls. The elevation of Idaho Falls is 4744 ft. The beginning of the Snake in Wyoming which makes the South Fork is at about 7400 ft. The Henry’s Fork begins at 6398 ft.
As the Snake makes its way from Idaho Falls it travels a bit south and then the river flows west across the entire state of Idaho. Outside of Twin Falls, the river begins to turn to the north-west. West of Boise, the capital of Idaho, the Snake makes a sharp turn and makes its way north up through Hells Canyon and onto Lewiston. The Snake then makes its way west into Washington where it joins the Columbia River. The river then makes its way west to the coast of Oregon.
The Teton River begins in Teton Valley Idaho. While much smaller than the Snake River, it does flow north for nearly half of its length. This river is a spring creek that is formed by many many springs at the south end of Teton Valley. Near the confluence of Fox Creek, the Teton is formed. Generally, the river begins at the White Bridge. The Teton river makes its way through the valley being fed by smaller streams. When the Teton river reaches Bitch Creek, it turns sharply to the West and makes its way to the Henry’s Fork near Rexburg Idaho.