370 Lakeside Triathlon

SEP

12

2027

A USAT‑sanctioned triathlon at 370 Lakeside Park offering distances from a 5K and sprints up to a half triathlon, with a beach swim, country‑road bike courses, and a finish festival.

Sun 12 Sep 2027

St. Peters, Missouri

Website Registration

Sprint 750 m 5 km Olympic 1500 m 10 km Middle distance 1.2 13.1 mi Sprint 750 m 23 km Super sprint 300 m 23 km 2 mi

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370 Lakeside Triathlon

The 370 Lakeside Triathlon is a USAT‑sanctioned multisport event held at 370 Lakeside Park in Saint Peters, Missouri. The race begins with a beach swim in the lake, follows with a bike course on country roads in St. Charles County, and finishes with a run on park trails. Packet pickup and bike drop take place the day before the race at the Corporate Pavilion; athletes must present photo ID and may leave bikes overnight in transition with provided security.

Registration includes a long sleeve hooded shirt, swim cap, finisher medal, live race results, race photos, awards, and a post‑race festival with music, food, and drinks. On‑course support includes a mechanic in transition and a SAG vehicle on the bike course. Athletes must hold a valid USA Triathlon membership or purchase a single‑event membership.

Race rules follow USA Triathlon standards; equipment and conduct rules apply in transition and on course. Timing chips, wristbands, bike and helmet stickers, and run bibs are required and distributed at packet pickup. The event enforces time cutoffs for each distance and may remove athletes who cannot meet posted cutoffs. A finish line festival provides food, vendors, music, and athlete meals; non‑athletes pay a small fee. Photographs may be taken and used for event purposes.

Race distances and options include: Visit the organization's website for the most recent information.