Three Forts Marathon
Worthing, United Kingdom · Tuesday 4 May 2027
The Three Forts Marathon, held in West Sussex, UK, is known as 'The Tough One' due to its challenging terrain and scenic route. The course spans 27.2 miles, including a total of approximately 3450 feet of climb, with stiles and rough tracks underfoot. Starting and finishing at Lancing Manor Leisure Centre, the race takes runners through picturesque landscapes and historic forts, offering breathtaking views of the South Downs.
Difficulty Calculator
h
:m
:s
Adjusted Time
6:07:32
Time difference: +127.5 minutes compared to a flat, road, temperate course.
Course Details
Elevation Gain1949m
Elevation High235m
Elevation Low2m
Weather Forecast
High14°C
Low7°C
Chance of Rain0%
How hard is Three Forts Marathon?
Very Difficultharder than 99% of marathons
Flattest / easiestHardest
On our difficulty model, Three Forts Marathon plays about 106 minutes slower than an average road marathon for a 3:30 runner. It ranks #10 hardest of 1150 marathons we analyse, and #1 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 Three Forts 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 Three Forts Marathon | Difference |
|---|---|---|
| 3:00:00 | 4:17:34 | +1:17:34 |
| 3:30:00 | 5:11:29 | +1:41:29 |
| 4:00:00 | 6:07:32 | +2:07:32 |
| 4:30:00 | 7:05:34 | +2:35:34 |
| 5:00:00 | 8:05:31 | +3:05:31 |
| 5:30:00 | 9:07:18 | +3:37:18 |
| 6:00:00 | 10:10:49 | +4:10:49 |
Use the calculator above for your exact goal time. Want a prediction from your own training? Try the marathon time predictor.
Three Forts Marathon 2027 Course Analysis
Three Forts Marathon is a full marathon held in Worthing, United Kingdom. It is scheduled for Tuesday 4 May 2027. The course is run on trail surface with 1949m of total climbing, with its high point near 235m above sea level. For registration and full race details, visit the official Three Forts Marathon website.
Elevation Profile
This is a very challenging course with 1949m of total climbing - well above the average trail marathon - topping out around 235m 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. Near-ideal running temperatures are expected, ranging from 7°C to 14°C. This temperature range is widely considered optimal for marathon performance, allowing efficient heat dissipation without cold-related issues. There is a low chance of rain (0%), so dry conditions are likely.
Surface Type: Trail
Three Forts Marathon is a trail race, meaning the course includes unpaved surfaces such as dirt, gravel, or forest paths. Trail surfaces are usually slower than the road equivalent - often by 10-20% - because of uneven footing, technical sections, and frequently steeper gradients, though a smooth, non-technical or downhill trail can run faster than that suggests. Trail-specific shoes with good grip are recommended.
Looking for an easier marathon or a tougher challenge? You can also compare Three Forts Marathon against other marathons to find the right race for your goals.
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