Columbia River Gorge National Scenic Area topographic map

Name: Columbia River Gorge National Scenic Area topographic map, elevation, terrain.

Location: Columbia River Gorge National Scenic Area, Klickitat County, Washington, United States (45.51048 -122.40348 45.80454 -120.87073)

Average elevation: 723 m

Minimum elevation: 17 m

Maximum elevation: 3,287 m

The Columbia River, Klamath River in northern California, Pit River in northern California, and Fraser River in southern British Columbia are the only four rivers connecting the watersheds on the east side of the Cascade Range to the Pacific Ocean. Each river has carved out a gorge through the Cascades. The Columbia River Gorge marks the state line between Oregon and Washington, and its wide range of elevation and precipitation makes it an extremely diverse and dynamic place. Ranging from 4,000 feet (1,200 m) to sea level, and transitioning from 100 inches (2,500 mm) of precipitation to only 10 inches (250 mm) in 80 miles (130 km), the gorge provides the setting for a diverse collection of ecosystems, from the temperate rain forest on the western end—with an average annual precipitation of 75 to 100 inches (1,900 to 2,500 mm)—to the eastern grasslands with average annual precipitation between 10 and 15 inches (250 and 380 mm), to a transitional dry woodland between Hood River and The Dalles. Isolated micro-habitats have allowed for many species of endemic plants and animals to prosper, including at least 13 endemic wildflowers.

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