Koosah Falls is a well-known waterfall on Oregon’s McKenzie River in the Willamette National Forest, south of Santiam Pass and west of Mount Washington. Also called Middle Falls, it is the second of the river’s three major waterfalls and sits about 0.5 miles downstream from Sahalie Falls. The waterfall is distinguished by a 64-foot main drop, where the river plunges into a substantial pool. Its name comes from Chinook Jargon, in which koosah means “sky,” linking the place to the region’s linguistic heritage as well as to the striking natural features that have made it notable along this stretch of the river.