Boise & Treasure Valley Triathlon Events

Boise and the Treasure Valley run Idaho's largest triathlon cluster. Ironman 70.3 Boise headlines in late May — a fast, flat course on the Boise River greenbelt that draws a national field. The Treasure Valley Triathlon serves the metro throughout the summer, and the Nampa Indoor Tri keeps the season alive year-round. For athletes who want more vertical, Idaho High Mountain Triathlon in Yellow Pine and the Mary Lou Triathlon in Weippe push into genuine backcountry. Hot summers, cold open water, and a finish-line scene that tends to involve potato-based food.