Naeba-Sanroku Geopark Tsunan Ultramarathon 80K

Race completed

80 km Distance

2,800 m Climbing

8.2 Grit · Hardcore

37.0143° N, 138.6525° E © OpenFreeMap © OpenMapTiles Data from OpenStreetMap

What the course asks

Climbing rate 35 m / km Rolling. Moderate undulations. Requires consistent effort across varying grades.

Time limit 15 hours 11:15 min/km average. Generous. Walkable throughout for most of the field. About average for a 50 mi. Measured against 446 races of the same distance. Cut-off calculator →

Field size ~51 Small. Long stretches with nobody in sight.

DUV results for the 2026 edition (80km) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.

Typical conditions, July

Daytime high 26°C

Night low 17°C

Rainfall Wet — expect rain

Daylight 14 h 38 m of light

Regional 2001-2020 average for July — NASA POWER, grid elevation 784 m. Not a forecast.

The Aid Station

Course-specific beta from the community

⛰️ terrain

This is a rolling course. Expect fast, runnable sections where rhythm is key.

By UltraHub Expert

👟 gear

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

By UltraHub Expert

Gear for this race

Chosen for 80 km of road with 2,800 m of ascent.

Trail Running Shoes 35 m of climb per kilometre — grip and rock protection before cushioning.
Race Nutrition 80 km of self-supported fuelling between aid stations.
Hydration Vests Pole attachment and chest-strap stability on steep ground.
Trekking Poles 2,800 m of ascent to walk up.
Headlamps A 15 h limit puts you out there after dark.