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About RaceIndexOur methodologyData coverageCyclingTriathlon

Three Forts Challenge

  • Lancing
  • South East
  • Rural
Data current as of

Official event website & entry ↗

Same event — which distance suits you?

DistanceAscentClimb densityDescentNet elevationMax absolute gradeGAP factor
Marathon922 m21.1 m/km922 m-0 m13.5%3.5%
Half Marathon463 m21.9 m/km463 m0 m16.4%3.3%
5 Mile172 m21.4 m/km172 m0 m14.8%3.6%

Marathon

Ascent
922 m
Climb density
21.1 m/km
Descent
922 m
Net elevation
-0 m
Max absolute grade
13.5%
GAP factor
3.5%

Half Marathon

Ascent
463 m
Climb density
21.9 m/km
Descent
463 m
Net elevation
0 m
Max absolute grade
16.4%
GAP factor
3.3%

5 Mile

Ascent
172 m
Climb density
21.4 m/km
Descent
172 m
Net elevation
0 m
Max absolute grade
14.8%
GAP factor
3.6%

GAP is modelled energy-cost change versus flat, not a time penalty. Unavailable cells mean no sourced value is available yet. Click a distance for its full page.

Compare distances at this event

Same-event questions

What distances does Three Forts Challenge offer?

Three Forts Challenge offers Marathon, Half Marathon, 5 Mile, all run from the same event.

Typical conditions on race weekend

  • 17°CTypical temperature
  • 16 kphTypical wind
  • 5 mmTypical rainfall
  • 65Favourability /100
Typical conditions for the race date and locality, warmer than the endurance-optimal window. These are climatological norms, not a forecast, and are shared across every distance at this event.

Explore each distance

How we calculated this

Published facts and derived model outputs on this page are tied to stored sources or a published, version-locked methodology. We show the provenance so runners, coaches and organisers can check it. Data on this page is current as of .

Derived numbers use scoring-methodology-v1.0.

Sources used on this page (3)

Read the full methodology →

Source-backed sections

available route profile, race-day conditions, and source facts are shown on this event page. Sections appear only when their source-backed data is available.