Innoko National Wildlife Refuge, National Wildlife Refuge in western Alaska, United States

Innoko National Wildlife Refuge covers 3,850,481 acres of western Alaska, making it the fifth-largest national wildlife refuge in the United States. Its northern unit, the 751,000-acre Kaiyuh Flats, borders the Yukon River southwest of Galena, while the southern unit of about 3,099,000 acres surrounds the Innoko River. The terrain is swampy, with 1,240,000 acres designated wilderness.

Congress established this refuge in 1980 through the Alaska National Interest Lands Conservation Act, a landmark law protecting vast wilderness areas. The creation reflected the nation's commitment to conserving Alaska's natural regions during that era.

The name Innoko comes from the Innoko River, which drains the refuge's southern unit; the northern unit is called Kaiyuh Flats, after the flats beside the Yukon. The refuge is administered from Galena, a community on the Yukon River, and the surrounding region is Dene (Athabascan) country. The Innoko River itself was a route for river travel and fish camps long before the refuge was created.

The refuge has no road access from outside and contains no roads; air access can be arranged in McGrath. The refuge is administered from offices in Galena, and the northern Kaiyuh Flats unit lies southwest of Galena along the Yukon River.

The northern unit is called Kaiyuh Flats, spelled with a "y" in the middle, and covers 751,000 acres beside the Yukon River southwest of Galena. The southern unit holds about 3,099,000 acres around the Innoko River. Together they make the refuge the fifth-largest national wildlife refuge in the United States, with 1,240,000 acres designated wilderness.