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| Event | Distance | When | Entry fee | Cap |
|---|---|---|---|---|
| Battle of Waterloo | Olympic TriathlonOpen water swim | Aug 1, 20277:30 AM | $330$348 after Dec 28, 2026 | 100 |
| Half the Battle | Half Iron TriathlonOpen water swim | Aug 1, 20277:30 AM | $210$228 after Dec 28, 2026 | – |
Entry fees exclude processing fees. Prices and dates come from the race's registration page and refresh nightly.
The Half Iron Triathlon fee goes up to $228 on Dec 28, 2026.
Around August 1, Grass Lake typically runs about 79°F at the surface (74 to 82°F across 2011 to 2020). The water usually runs above 78°F at this date: wetsuits are allowed but make you ineligible for age-group awards.
A model estimate from the USGS lake temperature model (daily surface temperatures for US lakes), not a measurement. Wetsuit cutoffs are USA Triathlon age-group rules. The race's own water temperature reading on race morning decides.
Online registration closes Jul 31, 2027, unless the race fills first.
Sunrise on race morning is at about 6:28 AM, and the Battle of Waterloo starts at 7:30 AM. The start sits about 1,010 feet above sea level.
Fees exclude processing fees. Comparisons use current entry fees and published results from races nearby.
11500 Seymour Road, Grass Lake, MI 49240
The pin marks the address the race lists, which is usually the start. Course maps are the organizers' own.
Around August 1 the day usually runs from 64°F at dawn to 82°F in the afternoon, with measurable rain on about 31% of days. Cold snaps dip to 58°F and hot years reach 87°F.
Based on 75 days within a week of the date over the last 5 years, from historical weather for the start area. Not a forecast.
What the organizers of Battle of Waterloo 10-Stage Adventure Triathlon cover on their registration page, in brief.
Schedule and packet pickup
WELCOME, TRIATHLETES! We are thrilled that you will be joining us for Battle of Waterloo! There is a whole lot of information to know in order to be prepared for race day, and you can find all of that in the Athlete Guide. Please note that…
Schedule and packet pickup
Aberdeen Bike will be on-site to help you with any last-minute bicycle needs before the start of the race! We also recommend visiting Aberdeen in Chelsea, MI before race day to make sure your bike is race-ready! Meet Kevin, owner of…
Schedule and packet pickup
We will do self-body-marking. Markers will be provided at packet pickup and race morning or you can mark yourself at home. You will write your number on each bicep and your age and race on the back of your left calf. Write BOW or Half for…
Schedule and packet pickup
Course Cutoffs & Timelines – What to Know. Cutoff #1. Full Battle participants must reach Leg #4 (Clear Lake exit) within 2 hours and 25 minutes of the race start. If you don’t make it by then—no worries! You’ll be rerouted to finish the…
Schedule and packet pickup
Packet Pickup – Day Before the Race. 📍 11500 Seymour Rd, Grass Lake, MI 49240. 🗓 Saturday, July 26, 2025. 🕑 2:00 PM – 4:00 PM. Pick up your packet early to get your bike stickers, swim cap, goodie bag, and race T-shirt. You’ll also have…
Course
Please note that in the interest of safety, all courses are subject to change at any time at the discretion of the race director. Battle of Waterloo: Ten legs — run, bike, swim, run, swim, run, swim, run, bike, run — for a total of…
Organize this race? Add details or a correction
REGISTRATION OPENS NOVEMBER 27, 2026
Featured in Triathlete Magazine as a bucket list tri, Battle of Waterloo has 10 legs totaling 42 miles that traverse the sprawling Waterloo Recreation Area, one of the most rugged and beautiful parks in the Midwest. You’ll bike paved remote roads, run winding dirt lanes, climb steep trails, and swim across three wilderness lakes… carrying your shoes and swim gear with you the entire time. Don’t have that much time? Try Half the Battle: six legs, 18 miles of the same terrain (OK, less than half, but Half the Battle is a great name!).