Eastern

Eastern Idaho covers the country east of the Snake River Plain, the agricultural-and-mountain region running from Idaho Falls northeast toward Yellowstone and the Teton Range. The terrain stacks dramatically — broad irrigated plains around Idaho Falls and Rexburg climbing east into the Teton Valley and the volcanic highlands of Island Park. Most of the western boundary of Yellowstone National Park sits within easy reach. Bonneville, Madison, Fremont, Jefferson, Teton, and Clark counties cover the region. Idaho Falls is the largest city; Rexburg holds Brigham Young University–Idaho; Driggs and Victor anchor the Teton Valley; Island Park, Ashton, and Saint Anthony cover the high country toward Yellowstone. The Henrys Fork and South Fork of the Snake hold the most prized fly fishing in the country; Harriman State Park, Mesa Falls Scenic Byway, and the St. Anthony Sand Dunes add the major public-land draws. Most trips here are Yellowstone-adjacent and fishing-driven. Idaho Falls makes a comfortable base for a Yellowstone visit through the West Entrance; the Teton Valley offers a quieter alternative to Jackson Hole on the Wyoming side; the Henrys Fork and South Fork carry the serious fly-fishing traffic. Summer is peak; winter brings snowmobiling at Island Park.