Jeju 100K

UTMB World Series

100.0km

October 2

Jeju,

South Korea

utmb·source

Set your ITRA PI

Estimated Finish

16:26:13

ITRA PI

Segment Details

1/9

+0.9% · 0.25km · 3m+ · 1m-

82m80m

0.00km0.25km

OSM ↗

highway

secondary 82%residential 18%

review

Elevation Profile

Trail 53% · Technical 8%Technical 8%

0.8TDI

109.8km

139.3FlatKM

4217m+

4221m−

1913max

59min

0:46

6.7km

2:02

13.1km

1:23

8.4km

1:09

12.2km

3:54

17.8km

1:35

12.8km

2:12

11.0km

1:46

9.6km

1:38

11.6km

OSM

AID

Distance

Time

Gain

Loss

Gels

Water

Salts

Segment

6.7km/6.7km

0:46/0:46

362m+

26m−

0.8×40g(31g)

0.6L

2(400mg)

19.9km/13.1km

2:48/2:02

980m+

155m−

2.0×40g(82g)

1.5L

4(800mg)

28.3km/8.4km

4:11/1:23

477m+

755m−

1.4×40g(56g)

1.0L

3(600mg)

40.5km/12.2km

5:20/1:09

160m+

594m−

1.2×40g(46g)

0.9L

2(400mg)

58.3km/17.8km

9:15/3:54

1472m+

1081m−

3.9×40g(157g)

2.9L

8(1600mg)

71.0km/12.8km

10:50/1:35

95m+

538m−

1.6×40g(64g)

1.2L

3(600mg)

82.0km/11.0km

13:02/2:12

459m+

264m−

2.2×40g(89g)

1.6L

4(800mg)

91.6km/9.6km

14:49/1:46

456m+

404m−

1.8×40g(71g)

1.3L

4(800mg)

103.2km/11.6km

16:26/1:38

206m+

639m−

1.1×40g(45g)

1.2L

3(600mg)

AID

Distance

Time

Gels

Water

Salts

Gradient Matrix

Extra

Select a gradient

Uphill

Downhill

>40%

30%

25%

20%

15%

10%

0.5

0.3

0.2

0.3

0.5

Uphill

>40%

30%

25%

20%

15%

10%

0.2

0.3

0.5

10%

15%

20%

25%

30%

>40%

Downhill

Technical sections presentDarker — steeper and longer

Extremes

Gradient Breakdown

36% / 39.0km26% / 28.7km38% / 42.1km

Uphill

30–40%×10.5km

25–30%×31.9km

20–25%×10.7km

15–20%×53.0km

10–15%×119.7km

3–10%×2223.0km

Downhill

30–40%×10.9km

25–30%×10.6km

20–25%×10.8km

15–20%×42.7km

10–15%×127.7km

3–10%×2429.5km

Peaks for this course have not been detected yet.

Skyrunning · ISFSource

ISF technical requirements

Average incline3.8%> 6.0%

Steep sections (30%+)1.2%≥ 5.0%

Max altitude1913 m> 2000 m

Vertical climb4217 m> 1300 m

Asphalt27.7%< 15.0%

UIAA Technical climbing8.2 kmGrade I–II

Possible levelnot enough requirements met to estimate a level

Level 10/1

Peak reachno detection

Level 21/3

Altitude ≥ 3000 m1913 m

Scrambling8218 m

Rocky footing0 m

Level 30/3

Via ferrata0 m

Glacier0 m

Exposed ridge0 m

About Jeju 100K

Jeju 100K is a 100 km ultra trail of TransJeju by UTMB 2025 in Jeju, South Korea. The race starts on October 2, 2025. The course climbs 4217 m+ and descends 4221 m−, between a low point of 59 m and a high point of 1913 m. By gradient, 36% of the distance is uphill, 38% downhill and 26% flat. The longest climb runs 9.9 km at an average 14.3% grade (1408 m of vertical). The longest descent runs 9.1 km at 12.7% (1160 m of vertical). Surface: 53% trail, 28% road, 9% smooth, and 8% technical. Flat-equivalent effort: 139.3 FlatKM.

835 finishers completed the 2025 edition. Men's winner: Jianjian Yang (China) in 10:10:51. Women's winner: Leslie Nowicki (France) in 13:02:58.

This page has the full results and splits, interactive elevation profile, gradient matrix, pacing and nutrition planner and weather climatology for Jeju 100K.

Other distances of TransJeju by UTMB 2025Jeju 100M (148 km)·Jeju 70K (70.0 km)

Other editions of Jeju 100K2026

Official websitetransjeju.utmb.world