Grandma's Marathon
Two Harbors, United States of America · Sunday 20 June 2027
Grandma's Marathon, held on June 21, 2025, in Duluth, Minnesota, is one of the most prestigious marathons in the U.S. The course takes runners along the scenic shores of Lake Superior, offering breathtaking views of the lake and surrounding landscape. With its fast and flat profile, this marathon is ideal for achieving personal bests and qualifying for the Boston Marathon.
Difficulty Calculator
h
:m
:s
Adjusted Time
3:57:25
Time difference: -2.6 minutes compared to a flat, road, temperate course.
Course Details
Elevation Gain91m
Elevation High219m
Elevation Low184m
Weather Forecast
High22°C
Low9°C
Chance of Rain19%
How hard is Grandma's Marathon?
Moderateharder than 27% of marathons
Flattest / easiestHardest
On our difficulty model, Grandma's Marathon plays about 2 minutes slower than an average road marathon for a 3:30 runner. It ranks #841 hardest of 1151 marathons we analyse, and #424 of 576 in United States of America. Use the calculator above to see the exact adjusted time for your own goal pace.
What will you run at Grandma's Marathon?
Estimated finish times on this course versus the same effort on an average road marathon, based on its elevation, surface, and expected race-day temperature.
| Average-course time | On Grandma's Marathon | Difference |
|---|---|---|
| 3:00:00 | 2:56:46 | −03:14 |
| 3:30:00 | 3:27:05 | −02:55 |
| 4:00:00 | 3:57:25 | −02:35 |
| 4:30:00 | 4:27:46 | −02:14 |
| 5:00:00 | 4:58:08 | −01:52 |
| 5:30:00 | 5:28:30 | −01:30 |
| 6:00:00 | 5:58:54 | −01:06 |
Use the calculator above for your exact goal time. Want a prediction from your own training? Try the marathon time predictor.
Grandma's Marathon 2027 Course Analysis
Grandma's Marathon is a full marathon held in Two Harbors, United States of America. It is scheduled for Sunday 20 June 2027. The course is run on road surface with 91m of total climbing, with its high point near 219m above sea level. For registration and full race details, visit the official Grandma's Marathon website.
Elevation Profile
This is a very flat course, with only 91m of total climbing and little change in altitude throughout. Flat profiles let you hold an even pace from start to finish, which makes this a fast, PB-friendly race.
Expected Race Day Weather
Based on historical weather data for June, the expected race day conditions are as follows. Moderate temperatures between 9°C and 22°C are expected. While comfortable for most runners, those targeting fast times should pay attention to hydration, as these temperatures can impact performance on race day. There is a low chance of rain (19%), so dry conditions are likely.
Surface Type: Road
Grandma's Marathon is run on road surfaces, which provide the fastest and most predictable conditions for racing. Road courses allow for consistent pacing and are typically the best choice for a personal best.
Looking for an easier marathon or a tougher challenge? You can also compare Grandma's Marathon against other marathons to find the right race for your goals.
Marathons of similar difficulty
If Grandma's Marathon fits your goal, these courses play out about the same on our difficulty model.
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