Clarendon Marathon
Winchester, United Kingdom · Monday 31 May 2027
Clarendon Marathon is a challenging off-road event that takes runners from Salisbury to Winchester along the ancient Clarendon Way. The course includes a few extra turns to make up the full 26.2 miles, with more than 90% of the route being off-road. The trail follows country tracks and paths that have remained unchanged since being used by ancient Kings and Queens of England.
Difficulty Calculator
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:m
:s
Adjusted Time
4:35:14
Time difference: +35.2 minutes compared to a flat, road, temperate course.
Course Details
Elevation Gain794m
Elevation High170m
Elevation Low29m
Weather Forecast
High23°C
Low10°C
Chance of Rain0%
How hard is Clarendon Marathon?
Very Difficultharder than 83% of marathons
Flattest / easiestHardest
On our difficulty model, Clarendon Marathon plays about 31 minutes slower than an average road marathon for a 3:30 runner. It ranks #193 hardest of 1151 marathons we analyse, and #17 of 57 in United Kingdom. Use the calculator above to see the exact adjusted time for your own goal pace.
What will you run at Clarendon 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 Clarendon Marathon | Difference |
|---|---|---|
| 3:00:00 | 3:17:06 | +17:06 |
| 3:30:00 | 3:55:41 | +25:41 |
| 4:00:00 | 4:35:14 | +35:14 |
| 4:30:00 | 5:15:40 | +45:40 |
| 5:00:00 | 5:56:56 | +56:56 |
| 5:30:00 | 6:38:59 | +1:08:59 |
| 6:00:00 | 7:21:46 | +1:21:46 |
Use the calculator above for your exact goal time. Want a prediction from your own training? Try the marathon time predictor.
Clarendon Marathon 2027 Course Analysis
Clarendon Marathon is a full marathon held in Winchester, United Kingdom. It is scheduled for Monday 31 May 2027. The course is run on road surface with 794m of total climbing, with its high point near 170m above sea level. For registration and full race details, visit the official Clarendon Marathon website.
Elevation Profile
This is a very challenging course with 794m of total climbing - well above the average road marathon - topping out around 170m above sea level. Hill training is essential, and you should expect a slower finish time than on a flat course.
Expected Race Day Weather
Based on historical weather data for May, the expected race day conditions are as follows. Moderate temperatures between 10°C and 23°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 (0%), so dry conditions are likely.
Surface Type: Road
Clarendon 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 Clarendon Marathon against other marathons to find the right race for your goals.
Marathons of similar difficulty
If Clarendon Marathon fits your goal, these courses play out about the same on our difficulty model.
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