Flat grade share
- Three Forts Challenge Marathon
- 29.8% Favoured
- Beachy Head Marathon
- 22.8%
Three Forts Challenge Marathon vs Beachy Head Marathon
A data-led head-to-head using sourced race facts and available derived figures under one published methodology.
Data current as ofThree Forts Challenge Marathon or Beachy Head Marathon — which comes out ahead?
Three Forts Challenge Marathon and Beachy Head Marathon split the available advantages, so the better choice depends on which metric matters most to the runner.
Route comparison snapshot
Three Forts Challenge Marathon
- Mapped route
- Held
- Elevation profile
- Held
- course flatness
- 3.5% Favoured
- flat grade share
- 29.8% Favoured
- lower ascent
- 922 m
- climbing density
- 21.1 m/km
- net elevation
- -0 m
- maximum grade
- 13.5%
Beachy Head Marathon
- Mapped route
- Held
- Elevation profile
- Held
- course flatness
- 6.3%
- flat grade share
- 22.8%
- lower ascent
- 1,144 m
- climbing density
- 27.1 m/km
- net elevation
- 1 m
- maximum grade
- 31.2%
| Metric | Three Forts Challenge Marathon | Beachy Head Marathon |
|---|---|---|
| Flat grade share | 29.8% ✓ | 22.8% |
| GAP factor (% slower than flat) | 3.5% ✓ | 6.3% |
| Uphill share | 35.8% | 39.3% |
| Steep-up share | 12.3% | 16.7% |
| Downhill share | 34.4% | 37.9% |
| Total ascent (m) | 922 m | 1,144 m |
| Climbing density (m/km) | 21.1 m/km | 27.1 m/km |
| Longest climb length (m) | 3,550 m | 2,340 m |
| Longest climb gain (m) | 201 m | 146 m |
| Longest climb average grade | 5.7% | 6.3% |
| Total descent (m) | 922 m | 1,143 m |
| Net elevation (m) | -0 m | 1 m |
| Max absolute grade | 13.5% | 31.2% |
| Start elevation (m) | 8 m | 49 m |
| Finish elevation (m) | 8 m | 51 m |
| Scenic score | 93/100 | 98/100 ✓ |
| Conditions | 65/100 | 67/100 ✓ |
GAP factor (% slower than flat)
- Three Forts Challenge Marathon
- 3.5% Favoured
Uphill share
- Beachy Head Marathon
- 39.3%
Steep-up share
- Beachy Head Marathon
- 16.7%
Downhill share
- Beachy Head Marathon
- 37.9%
Total ascent (m)
- Beachy Head Marathon
- 1,144 m
Climbing density (m/km)
- Three Forts Challenge Marathon
- 21.1 m/km
- Beachy Head Marathon
- 27.1 m/km
Longest climb length (m)
- Beachy Head Marathon
- 2,340 m
Longest climb gain (m)
- Beachy Head Marathon
- 146 m
Longest climb average grade
Total descent (m)
- Beachy Head Marathon
- 1,143 m
Net elevation (m)
Max absolute grade
- Beachy Head Marathon
- 31.2%
Start elevation (m)
Finish elevation (m)
Scenic score
- Beachy Head Marathon
- 98/100 Favoured
Conditions
- Beachy Head Marathon
- 67/100 Favoured
Only metrics available for at least one side are shown. A ✓ marks the better value for each metric (higher-is-better aware). Scores are out of 100 when available. Ascent, climbing density, max absolute grade and median finish describe course or field context and are not marked as better or worse.
Race facts that change the decision
| Fact | Three Forts Challenge Marathon | Beachy Head Marathon |
|---|---|---|
| Schedule | Exact race date not confirmed. Event weekend starts 2027-05-02 (legacy event-level date). | Exact race date not confirmed. Event weekend starts 2026-10-24 (legacy event-level date). |
| Location | Lancing, South East | Eastbourne, South East |
| Actual distance | 43.8 km | 42.2 km |
| raceindex.org mapped route held | Held | Held |
| raceindex.org elevation profile held | Held | Held |
| Course type | Loop | Trail |
| Surface | Hilly and challenging over chalk, flint and grass paths with stiles and rough tracks underfoot; minimal road sections. | Off Road |
| Elevation character | Hilly | Hilly |
| Terrain | Trail | Trail, Mixed, Road |
| Scenery | Countryside, Historic, Coastal, Riverside | Coastal, Parkland, Countryside, Forest, Riverside, Waterfront |
| Atmosphere | Community, Charity, Scenic Tour | Scenic Tour, Destination |
| Technicality | Moderate | Moderate |
| Total ascent | 922 m | 1,144 m |
| Climbing density | 21.1 m/km | 27.1 m/km |
| Total descent | 922 m | 1,143 m |
| Net elevation | -0 m | 1 m |
| Max absolute grade | 13.5% | 31.2% |
| Flat grade share | 29.8% | 22.8% |
| GAP factor | 3.5% | 6.3% |
| Cutoff | 6:00:00 | 9:00:00 |
| Entry model | Open | Open |
Schedule
- Three Forts Challenge Marathon
Exact race date not confirmed. Event weekend starts 2027-05-02 (legacy event-level date).
- Beachy Head Marathon
Exact race date not confirmed. Event weekend starts 2026-10-24 (legacy event-level date).
Location
- Three Forts Challenge Marathon
- Lancing, South East
- Beachy Head Marathon
- Eastbourne, South East
Actual distance
- Three Forts Challenge Marathon
- 43.8 km
- Beachy Head Marathon
- 42.2 km
raceindex.org mapped route held
- Three Forts Challenge Marathon
- Held
- Beachy Head Marathon
- Held
raceindex.org elevation profile held
- Three Forts Challenge Marathon
- Held
- Beachy Head Marathon
- Held
Course type
- Three Forts Challenge Marathon
- Loop
- Beachy Head Marathon
- Trail
Surface
- Three Forts Challenge Marathon
- Hilly and challenging over chalk, flint and grass paths with stiles and rough tracks underfoot; minimal road sections.
- Beachy Head Marathon
- Off Road
Elevation character
- Three Forts Challenge Marathon
- Hilly
- Beachy Head Marathon
- Hilly
Terrain
- Three Forts Challenge Marathon
- Trail
- Beachy Head Marathon
- Trail, Mixed, Road
Scenery
- Three Forts Challenge Marathon
- Countryside, Historic, Coastal, Riverside
- Beachy Head Marathon
- Coastal, Parkland, Countryside, Forest, Riverside, Waterfront
Atmosphere
- Three Forts Challenge Marathon
- Community, Charity, Scenic Tour
- Beachy Head Marathon
- Scenic Tour, Destination
Technicality
- Three Forts Challenge Marathon
- Moderate
- Beachy Head Marathon
- Moderate
Total ascent
- Three Forts Challenge Marathon
- 922 m
- Beachy Head Marathon
- 1,144 m
Climbing density
- Three Forts Challenge Marathon
- 21.1 m/km
- Beachy Head Marathon
- 27.1 m/km
Total descent
- Three Forts Challenge Marathon
- 922 m
- Beachy Head Marathon
- 1,143 m
Net elevation
- Three Forts Challenge Marathon
- -0 m
- Beachy Head Marathon
- 1 m
Max absolute grade
- Three Forts Challenge Marathon
- 13.5%
- Beachy Head Marathon
- 31.2%
Flat grade share
- Three Forts Challenge Marathon
- 29.8%
- Beachy Head Marathon
- 22.8%
GAP factor
- Three Forts Challenge Marathon
- 3.5%
- Beachy Head Marathon
- 6.3%
Cutoff
- Three Forts Challenge Marathon
- 6:00:00
- Beachy Head Marathon
- 9:00:00
Entry model
- Three Forts Challenge Marathon
- Open
- Beachy Head Marathon
- Open
Facts are shown only when they exist in the sourced race record; Not held means no sourced value is held for that race.
Common questions
Which is flatter, Three Forts Challenge Marathon or Beachy Head Marathon?
Three Forts Challenge Marathon has the lower GAP factor, making it the flatter course on our route model and more favourable on gradient alone.