The Yukon Flats are a vast area of wetlands, forest, bog, and low-lying ground centered on the confluence of the Yukon River, Porcupine River, and Chandalar River in the central portion of the U.S. state of Alaska. The Yukon Flats are bordered in the north by the Brooks Range, in the south by the White Mountains, and cover an area of approximately . The Yukon Flats are a critical waterfowl breeding ground due to the large area of wetland provided by the estimated 40,000 small lakes and streams in the area. In recognition of this fact, the area is protected under the Yukon Flats National Wildlife Refuge. The Yukon Flats straddle the Arctic Circle and have an extremely variable climate. Temperatures of 95 F (35 °C) are not uncommon in summer, while winter temperatures have been known to drop to -70 F (-57 °C).