There are 3 US Post Offices in Teton County serving a total of 9,846 residents equating to 3,282 residents per post office. It's estimated that approximately 15,715 packages are handled across the 3 county post offices annually. Teton County is a county located in the U.S. state of Idaho. As of the 2010 census, the population was 10,170. The county seat is Driggs, and the largest city is Victor. The county was established in 1915 and was named after the Teton Mountains to the east. Teton County is part of the Jackson, WY-ID Micropolitan Statistical Area. The Teton Valley was discovered by John Colter in 1808, a member of the Lewis and Clark Expedition (1804\u201306). It became known as Pierre's Hole, and it hosted the well-attended 1832 Rendezvous, which was followed by the Battle of Pierre's Hole."