Come race IRONMAN 70.3 Chattanooga 2023. Chattanooga, known as the Scenic City, features Lookout Mountain, the Tennessee River and endless opportunities to explore. This course brings a unique PR setting downriver 1.4 mile swim, epic rollers on the bike through the historic Chickamauga and a run through downtown Chattanooga. From leisurely adventures or epic all day exploration, there’s something for everyone. Endless adventures for all.