Welcome from the Hardin KOA. First things first: We are excited for another season in beautiful Montana. Due to daily changing rules and regulations, please call ahead - 406 665 1635. Office hours: 10 am to 6 pm MSTThe Hardin KOA is halfway between Yellowstone National Park and Mt. Rushmore. Come stay with us and enjoy all that our area has to offer. You'll be glad you did!