Umiat (OO-mee-yat) is an unincorporated community in North Slope Borough, Alaska, United States. It is located on the Colville River, 140 miles southwest of Deadhorse in the Arctic Circle. The town is not accessible by road or rail, only by air or river. In 1944, the Naval Oil Reserve was set up and it later became an air force base, which is now closed. It is known as one of the coldest places in the US with its inland tundra climate, a rarity for North America. Yearly low temperatures run even colder than Utqiaġvik, Alaska on average.