Flat grade share
- Two Tunnels Railway Races Marathon
- 71.5% Favoured
Two Tunnels Railway Races Marathon vs Portland Coastal Marathon
A data-led head-to-head using sourced race facts and available derived figures under one published methodology.
Data current as ofTwo Tunnels Railway Races Marathon or Portland Coastal Marathon — which comes out ahead?
Two Tunnels Railway Races Marathon and Portland Coastal Marathon split the available advantages, so the better choice depends on which metric matters most to the runner.
Route comparison snapshot
Two Tunnels Railway Races Marathon
- Mapped route
- Held
- Elevation profile
- Held
- course flatness
- 2.0% Favoured
- flat grade share
- 71.5% Favoured
- lower ascent
- 415 m
- climbing density
- 9.8 m/km
- net elevation
- 2 m
- maximum grade
- 21.0%
Portland Coastal Marathon
- Mapped route
- Held
- Elevation profile
- Held
- course flatness
- 4.0%
- flat grade share
- 53.2%
- lower ascent
- 715 m
- climbing density
- 16.9 m/km
- net elevation
- -0 m
- maximum grade
- 33.0%
| Metric | Two Tunnels Railway Races Marathon | Portland Coastal Marathon |
|---|---|---|
| Flat grade share | 71.5% ✓ | 53.2% |
| GAP factor (% slower than flat) | 2.0% ✓ | 4.0% |
| Uphill share | 16.6% | 23.4% |
| Steep-up share | 5.7% | 8.6% |
| Downhill share | 11.9% | 23.5% |
| Total ascent (m) | 415 m | 715 m |
| Climbing density (m/km) | 9.8 m/km | 16.9 m/km |
| Longest climb length (m) | 1,920 m | 680 m |
| Longest climb gain (m) | 99 m | 99 m |
| Longest climb average grade | 5.1% | 14.6% |
| Total descent (m) | 413 m | 715 m |
| Net elevation (m) | 2 m | -0 m |
| Max absolute grade | 21.0% | 33.0% |
| Start elevation (m) | 41 m | -0 m |
| Finish elevation (m) | 43 m | -0 m |
| Value | 79/100 | Unavailable |
| Scenic score | 77/100 | 87/100 ✓ |
| Conditions | 62/100 | 78/100 ✓ |
| Entry fee (GBP) | £60 | Unavailable |
| Lowest modelled true cost (GBP) | £190 | Unavailable |
GAP factor (% slower than flat)
- Two Tunnels Railway Races Marathon
- 2.0% Favoured
Uphill share
Steep-up share
Downhill share
Total ascent (m)
Climbing density (m/km)
- Portland Coastal Marathon
- 16.9 m/km
Longest climb length (m)
Longest climb gain (m)
Longest climb average grade
Total descent (m)
Net elevation (m)
Max absolute grade
Start elevation (m)
Finish elevation (m)
Value
- Portland Coastal Marathon
- Unavailable
Scenic score
- Portland Coastal Marathon
- 87/100 Favoured
Conditions
- Portland Coastal Marathon
- 78/100 Favoured
Entry fee (GBP)
- Portland Coastal Marathon
- Unavailable
Lowest modelled true cost (GBP)
- Portland Coastal Marathon
- Unavailable
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 | Two Tunnels Railway Races Marathon | Portland Coastal Marathon |
|---|---|---|
| Schedule | Exact race date not confirmed. Event weekend starts 2026-08-16 (legacy event-level date). | Exact race date not confirmed. Event weekend starts 2027-02-14 (legacy event-level date). |
| Location | Bath, South West | Portland, South West |
| Actual distance | 42.2 km | 42.2 km |
| raceindex.org mapped route held | Held | Held |
| raceindex.org elevation profile held | Held | Held |
| Course type | Unavailable | Laps |
| Surface | Unavailable | Coastal trail on the South West Coast Path (exposed limestone peninsula terrain). |
| Laps | 2 | Unavailable |
| Elevation character | Gently Rolling | Hilly |
| Terrain | Mixed, Towpath, Trail | Trail |
| Scenery | Parkland, Countryside, Riverside, City, Historic, Forest | Island, Coastal, Waterfront, City, Historic |
| Atmosphere | Scenic Tour, Community | Scenic Tour, Wilderness |
| Technicality | Non Technical | Moderate |
| Total ascent | 415 m | 715 m |
| Climbing density | 9.8 m/km | 16.9 m/km |
| Total descent | 413 m | 715 m |
| Net elevation | 2 m | -0 m |
| Max absolute grade | 21.0% | 33.0% |
| Flat grade share | 71.5% | 53.2% |
| GAP factor | 2.0% | 4.0% |
| Entry model | Open | Open |
| Entry fee | £60 | Unavailable |
| Lowest modelled true cost | £190 | Unavailable |
| Cost model origin | National Average | Unavailable |
| Measured course | Unavailable | No |
Schedule
- Two Tunnels Railway Races Marathon
Exact race date not confirmed. Event weekend starts 2026-08-16 (legacy event-level date).
- Portland Coastal Marathon
Exact race date not confirmed. Event weekend starts 2027-02-14 (legacy event-level date).
Location
- Two Tunnels Railway Races Marathon
- Bath, South West
- Portland Coastal Marathon
- Portland, South West
Actual distance
- Two Tunnels Railway Races Marathon
- 42.2 km
- Portland Coastal Marathon
- 42.2 km
raceindex.org mapped route held
- Two Tunnels Railway Races Marathon
- Held
- Portland Coastal Marathon
- Held
raceindex.org elevation profile held
- Two Tunnels Railway Races Marathon
- Held
- Portland Coastal Marathon
- Held
Course type
- Two Tunnels Railway Races Marathon
- Unavailable
- Portland Coastal Marathon
- Laps
Surface
- Two Tunnels Railway Races Marathon
- Unavailable
- Portland Coastal Marathon
- Coastal trail on the South West Coast Path (exposed limestone peninsula terrain).
Laps
- Two Tunnels Railway Races Marathon
- 2
- Portland Coastal Marathon
- Unavailable
Elevation character
- Two Tunnels Railway Races Marathon
- Gently Rolling
- Portland Coastal Marathon
- Hilly
Terrain
- Two Tunnels Railway Races Marathon
- Mixed, Towpath, Trail
- Portland Coastal Marathon
- Trail
Scenery
- Two Tunnels Railway Races Marathon
- Parkland, Countryside, Riverside, City, Historic, Forest
- Portland Coastal Marathon
- Island, Coastal, Waterfront, City, Historic
Atmosphere
- Two Tunnels Railway Races Marathon
- Scenic Tour, Community
- Portland Coastal Marathon
- Scenic Tour, Wilderness
Technicality
- Two Tunnels Railway Races Marathon
- Non Technical
- Portland Coastal Marathon
- Moderate
Total ascent
- Two Tunnels Railway Races Marathon
- 415 m
- Portland Coastal Marathon
- 715 m
Climbing density
- Two Tunnels Railway Races Marathon
- 9.8 m/km
- Portland Coastal Marathon
- 16.9 m/km
Total descent
- Two Tunnels Railway Races Marathon
- 413 m
- Portland Coastal Marathon
- 715 m
Net elevation
- Two Tunnels Railway Races Marathon
- 2 m
- Portland Coastal Marathon
- -0 m
Max absolute grade
- Two Tunnels Railway Races Marathon
- 21.0%
- Portland Coastal Marathon
- 33.0%
Flat grade share
- Two Tunnels Railway Races Marathon
- 71.5%
- Portland Coastal Marathon
- 53.2%
GAP factor
- Two Tunnels Railway Races Marathon
- 2.0%
- Portland Coastal Marathon
- 4.0%
Entry model
- Two Tunnels Railway Races Marathon
- Open
- Portland Coastal Marathon
- Open
Entry fee
- Two Tunnels Railway Races Marathon
- £60
- Portland Coastal Marathon
- Unavailable
Lowest modelled true cost
- Two Tunnels Railway Races Marathon
- £190
- Portland Coastal Marathon
- Unavailable
Cost model origin
- Two Tunnels Railway Races Marathon
- National Average
- Portland Coastal Marathon
- Unavailable
Measured course
- Two Tunnels Railway Races Marathon
- Unavailable
- Portland Coastal Marathon
- No
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, Two Tunnels Railway Races Marathon or Portland Coastal Marathon?
Two Tunnels Railway Races Marathon has the lower GAP factor, making it the flatter course on our route model and more favourable on gradient alone.