Dorking, United Kingdom · Saturday, June 20, 2026

Fixed Distance 100K

Hydra 75 Mile Ultra

Race completed
121 km Distance
not publishedn/a Climbing
6.1 est Grit · Hardcore

Calculated from 121 km alone — the organiser has not published an elevation profile. Read 6.1 as a floor, not a verdict.

51.2323° N, 0.3338° W© OpenFreeMap © OpenMapTiles Data from OpenStreetMap

What the course asks

Time limit 30 hours 14:53 min/km average. Generous. Walkable throughout for most of the field. Climbing is unpublished, so this pace is a ceiling on the effort, not a measure of it. Among the most forgiving 100K cut-offs we track. Measured against 208 races of the same distance. Cut-off calculator →

Typical conditions, June

Daytime high 20°C
Night low 11°C
Rainfall Mostly dry
Daylight 16 h 35 m of light

Regional 2001-2020 average for June — NASA POWER, grid elevation 51 m. Not a forecast.

The Aid Station

Course-specific beta from the community

👟 gear

With road terrain, choose a shoe with moderate cushioning for optimal performance.

By UltraHub Expert
🥤 nutrition

For 100km+ efforts, prioritize real food at aid stations to prevent palate fatigue.

By UltraHub Expert

Gear for this race

Chosen for 121 km of road.

  • Trail Running Shoes121 km of road — cushioning that is still there in the last quarter.
  • Race NutritionPast 121 km the palate quits before the legs do — carry more than one flavour.
  • Hydration VestsFlask capacity for 121 km, without the bounce.
  • HeadlampsA 30 h limit puts you out there after dark.
  • AccessoriesChafe and blisters end more 121 km races than fitness does.
All gear guides →

Course Notes

1mi loop (flat).

Similar races

Other 100K road ultras, closest in distance first.