Hells Canyon, River canyon between Oregon and Idaho, United States.

Hells Canyon is a river gorge between Oregon and Idaho, carved by the Snake River into layered rock. The depth reaches roughly 2,400 meters (around 8,000 feet), making this the deepest gorge on the continent.

Nez Perce and Shoshone tribes lived along the river for thousands of years, relying on salmon runs for food. White settlers arrived in the 1860s seeking gold, which displaced the original way of life.

The Nez Percé were the earliest known residents, joined by Shoshone-Bannock, Northern Paiute and Cayuse visitors; mild winters and plentiful plants and wildlife drew them. Pictographs and petroglyphs on the canyon walls record these settlements. In May 1887, 34 Chinese gold miners were ambushed and killed here in the Hells Canyon Massacre, and no one was held accountable.

Three access roads lead to different viewpoints along the river, with campgrounds and information stations near the trailheads. Spring and fall offer the mildest weather, while midsummer can become very hot at the bottom.

Most of the canyon lies within 214,000 acres of designated wilderness, and no road crosses it; only three spur roads reach the rim or the river. The Snake River was first run by river runners in 1928, and the three dams built between 1958 and 1967 supply about 70 percent of Idaho's hydroelectricity.