AI synthesis with sources · 4 min · edition 2027
The 70.3 Muskoka Bike Course: 90 km, 29 Climbs and Nowhere to Hide
Out-and-back toward Lake of Bays with 950-1,130 m of climbing depending on the source: easy gearing, conservative pacing and watch the pavement.
The course in a nutshell
90 km out-and-back from the Canada Summit Centre in Huntsville: Brunel Rd to Baysville, then HWY 117 to the turnaround and back the same way. Scenic, with the woods and lakes of cottage country, but not easy. Sources disagree on the elevation gain: between ~950 and ~1,130 m depending on who's measuring. Either way, it's a genuinely hilly bike leg, not just "rolling."
Heads up: the official 2027 page hasn't published the course yet. These details come from the 2024 athlete guide and public sources. Check the 2027 guide before you plan.
The climbs: 29, and some of them sting
The course profile analysis counts 29 significant climbs. The first ramp hits right away, at km 1, with pitches up to 19.6%. Others reach 14.6%, 13% and 12.5%. None are long in the alpine sense, but they add up: there's never a flat stretch long enough to truly recover in the aero position.
What to do, in practical terms:
- Easy gearing. Compact up front and at least a 32-34 in the back. On 19% ramps with race-day legs, a 28 forces you above threshold.
- Print out the climb chart and tape it to your top tube: it's a practice reported by the sources and helps you dose your effort knowing what's still to come.
- Train on steep ramps: short repeats above 10%, seated too, in the weeks before.
Pacing: the race is won on the way back
On a hilly out-and-back, the classic mistake is burning watts in the first 45 km while your legs are fresh. Keep the climbs under control: on ramps this steep, power spikes happen without you even noticing. Use the descents and false flats to recover and eat. Remember that a half marathon with 260-300 m of climbing awaits, starting uphill right away: every watt you save here, you'll find there.
Pavement, traffic and bike handling
The pavement is mostly good but with rough rural sections. One race report even mentions a loose headset at the end of the race: check your bike before check-in and pick clean lines on the descents. The road is open to traffic in some sections and reports mention fast-moving cars: stay strictly to the right, and be extra careful at the turnaround and when passing.
Road bike or TT bike?
Many athletes ride a road bike with clip-on aero bars, and on this course it's a sensible choice: the steep climbs and technical descents reward handling and gearing more than pure aerodynamics. If you ride the TT bike, mount a generous cassette anyway.
Aid stations and cutoffs
Three aid stations: km 24, 46 and 66, with Gatorade, water, Spark gels and Diesel bars. Three stops over 90 hilly km isn't a lot: start with adequate supplies on board and use the aid stations as a top-up, not your main plan.
Bike cutoff: 5h30, with intermediate cutoff points along the course (2024 guide data, to be verified for 2027). For reference, ballpark times range from ~2:30 for a top age-grouper to ~3:40 for a relaxed finisher: estimates, not official data.
What to do now
1. Mount easy gearing and test it on ramps above 10%. 2. Do at least a couple of long hilly rides with an uphill brick run right after. 3. Prepare the climb chart to print out. 4. Have your bike checked (headset included) before leaving for Canada.