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370 Lakeside Triathlon

Saint Peters, MissouriField of 120
Registration pagemseracing.com

At a glance

Last held
Aug 23, 2026
Next edition
2027 date not announced. Usually held in August.
Location
Saint Peters, Missouri
Distances
5K, Relay

Listed from RunSignUp. Checked Aug 23, 2026.

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About this race

Join us for the 6th annual USAT sanctioned 370 Lakeside Triathlon! Enjoy the flattest, fastest course starting in beautiful 370 Lakeside Park! Enjoy a beach start, amazing country roads in St. Charles County, and a run that includes the park trails. We offer a variety of race options from a 5k run, super sprint or sprint for newbies, up to half distance along with duathlon, aquabike and aquathlon options! 

For more information including course maps, schedule of events, race options, volunteer signup, etc. Please visit - https://www.mseracing.com/370-lakeside-triathlon

All athletes MUST show a Photo ID and pick up their own race packet, NO EXCEPTIONS.

Key dates

Tier 1 ends

Mar 18, 2025

Tier 2 ends

Jul 4, 2025

Tier 1 ends

Aug 11, 2025

Tier 3 ends

Aug 11, 2025

Tier 4 ends

Aug 14, 2025

Tier 2 ends

Aug 16, 2025

Tier 4 ends

Aug 16, 2025

Tier 4 ends

Aug 17, 2025

Tier 1 ends

Mar 24, 2026

Tier 2 ends

Jul 10, 2026

Tier 1 ends

Aug 17, 2026

Tier 3 ends

Aug 17, 2026

Tier 2 ends

Aug 22, 2026

Tier 4 ends

Aug 22, 2026

Registration closes

Aug 23, 2026

Race day

Aug 23, 2026

Tier 4 ends

Aug 23, 2026

Pricing

5k Run

Tier 4 ended Aug 22, 2026

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Collegiate Super Sprint Triathlon

Standard ended Aug 26, 2023

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HALF AQUABIKE

Tier 4 ended Aug 22, 2026

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HALF AQUATHLON

Tier 4 ended Aug 22, 2026

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Half Distance Aquabike

Tier 3 ended Aug 26, 2023

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Half Distance Duathlon

Tier 3 ended Aug 26, 2023

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Half Distance Duathlon (NEW)

Standard ended Aug 28, 2022

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Half Distance Relay

Standard ended Aug 26, 2022

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Half Distance Triathlon

Tier 3 ended Aug 26, 2023

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Half Distance Triathlon Relay

Tier 2 ended Aug 26, 2023

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HALF DUATHLON

Tier 4 ended Aug 22, 2026

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HALF INDIVIDUAL TRI

Tier 4 ended Aug 22, 2026

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HALF RELAY TRI

Tier 4 ended Aug 22, 2026

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Olympic Aquabike

Tier 4 ended Aug 22, 2026

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OLYMPIC AQUATHLON

Tier 4 ended Aug 22, 2026

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Olympic Distance Duathlon

Tier 3 ended Aug 26, 2023

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Olympic Distance Duathlon (NEW)

Standard ended Aug 28, 2022

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Olympic Distance Relay

Standard ended Aug 27, 2022

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Olympic Distance Triathlon

Tier 3 ended Aug 26, 2023

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OLYMPIC DUATHLON

Tier 4 ended Aug 22, 2026

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OLYMPIC ELITE TRIATHLON

Tier 2 ended Aug 16, 2025

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OLYMPIC INDIVIDUAL TRI

Tier 4 ended Aug 23, 2026

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OLYMPIC RELAY TRI

Tier 4 ended Aug 22, 2026

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Olympic Triathlon Relay

Tier 2 ended Aug 26, 2023

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Para-Triathlon Sprint Relay

Standard ended Aug 26, 2023

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Paratriathlon Sprint Distance

Standard ended Aug 26, 2022

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Paratriathlon Sprint Triathlon

Standard ended Aug 26, 2023

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Sprint Aquabike

Tier 4 ended Aug 22, 2026

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SPRINT AQUATHLON

Tier 4 ended Aug 22, 2026

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SPRINT COLLEGIATE TRI

Tier 2 ended Aug 22, 2026

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Sprint Distance Duathlon

Tier 3 ended Aug 26, 2023

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Sprint Distance Duathlon (NEW)

Standard ended Aug 28, 2022

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Sprint Distance Relay

Standard ended Aug 27, 2022

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SPRINT DUATHLON

Tier 4 ended Aug 22, 2026

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SPRINT HIGH SCHOOL TRI

Tier 2 ended Aug 22, 2026

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SPRINT INDIVIDUAL TRI

Tier 4 ended Aug 23, 2026

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SPRINT PARA MY TEAM TRIUMPH

Tier 2 ended Aug 22, 2026

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SPRINT PARA RELAY TRI

Tier 4 ended Aug 16, 2025

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SPRINT PARA TRI

Tier 2 ended Aug 22, 2026

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SPRINT RELAY TRI

Tier 4 ended Aug 22, 2026

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Sprint Triathlon

Tier 3 ended Aug 26, 2023

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Sprint Triathlon Relay

Tier 2 ended Aug 26, 2023

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SUPER SPRINT INDIVIDUAL TRI

Tier 4 ended Aug 22, 2026

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Super Sprint Triathlon

Tier 3 ended Aug 26, 2023

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