East central Idaho consists of nine diverse counties from Bonneville, Jefferson and Custer to the western border of Wyoming and the southern Montana border. The large mountains, deep rivers and fertile valleys give the area beauty and diversity. All nine counties are heavily involved in agriculture and related industries such as wholesale foods and food processing. The Idaho National Laboratory, one of the state’s largest employers, is also located here, attracting workers from eight of the nine counties. All counties benefit from the laboratory as its close involvement with economic development. The city of Idaho Falls, the regional hub for retail and medical services, is located in Bonneville County. Rexburg in Madison County is home to Brigham Young University–Idaho. The region is a gateway to Yellowstone National Park, and hundreds of thousands of tourists pass through it annually on U.S. Highway 20. Other tourist attractions include Craters of the Moon National Monument, Palisades Reservoir, Island Park Reservoir, Henry’s Lake and its worldwide reputation for fly fishing, Redfish Lake, Yellowstone Bear World, Harriman State Park and Borah Peak, the highest elevation in Idaho. Butte County is known as home of the world’s first nuclear power plant, the EBR-1, and for having the first city in the world, Arco, to be lit by atomic power.