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SEOUL 100K

SEOUL 100K takes place on Sat, Sep 19, 2026 in Seoul, South Korea. The main route is 100 km.

Date
Sat, Sep 19, 2026
Start
Seoul 🇰🇷
Distance
100 km
Level
Open to all
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Seoul 100K is an international ultra trail running race showcasing a blend of nature and urban landscapes by traversing mountains, rivers, and historic landmarks in Seoul.

Official event page

What this race demands

Seoul 100K requires continuous locomotion across 100 kilometers of mixed mountain, river, and urban terrain in Seoul during September.

Ultra-distance endurance

Covering 100 kilometers demands sustained aerobic capacity and the muscular endurance to keep moving for many consecutive hours.

Terrain versatility

Traversing mountains, rivers, and historic urban landmarks requires the adaptability to transition between technical trail surfaces and hard ground efficiently.

Given the ultra-distance format requiring many hours of continuous exertion, athletes should target 60 to 90 grams of carbohydrates per hour to sustain energy output.

Your road to race day

Race day at SEOUL 100K is 4 weeks away. This is how a coach divides that time. The first phase starts now.

  1. 01Peak1 week · Aug 23, 2026 Aug 29, 2026

    The hardest weeks of the plan: race-specific intensity at nearly full training load, sharpening exactly what this race asks for.

  2. 02Taper2 weeks · Aug 30, 2026 Sep 12, 2026

    Volume drops while intensity stays: short, sharp efforts keep the legs awake as fatigue drains away.

  3. 03Race week1 week · Sep 13, 2026 Sep 19, 2026

    Openers, rest and logistics. The work is done; the job now is arriving fresh.

Get this plan built around your own fitness

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