The 2025 event has concluded.

St. Lawrence Marathon

Cornwall, ON, Canada • April 26, 2025
TopDescriptionCourseCommunity

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rain Cloudy skies throughout the day with rain.

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A Boston-qualifier marathon that follows the beautiful St Lawrence River from Crysler Park Marina to St. Lawrence College in Cornwall, Ontario. As well as Half-Marathon, 10km and 5km distances that follow the scenic Great Lakes Waterfront Trail. Source

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When is the 2025 St. Lawrence Marathon?

The 2025 St. Lawrence Marathon will be held on Saturday April 26, 2025.

Is the St. Lawrence Marathon a Boston Marathon Qualfier?

Yes, the St. Lawrence Marathon is an official Boston Marathon qualifier.

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Historical Weather & Results

RunScore
Run Score: 6
Temp
53°F
Min/Max
44°/56°F
Dew
37°F
Days of Rain
2/3
Wind
14mph
Tap a row for details.
YearLow / HighRain

St. Lawrence Marathon 2024 Weather History

Becoming cloudy in the afternoon with rain.

2024
clear-day
46°/ 71°-
Run Score: 8

St. Lawrence Marathon 2023 Weather History

Partly cloudy throughout the day with rain.

2023
partly-cloudy-day
47°/ 55°Light
Run Score: 7

St. Lawrence Marathon 2019 Weather History

Partly cloudy throughout the day with a chance of rain throughout the day.

2019
rain
39°/ 42°Light
Run Score: 5
You Need an Account For That

Setting up a racecast.io account will allow you to start building a reputation in the community. Over time you'll be able to rate races, join the discussion, and post in the community.

Right now we are invite only, you can get on the waitlist by entering your email below:

OR
You Need an Account For That

Setting up a racecast.io account will allow you to start building a reputation in the community. Over time you'll be able to rate races, join the discussion, and post in the community.

Right now we are invite only, you can get on the waitlist by entering your email below:

OR