Altigraphs
HC

Col de Porte

Southern ascent from Grenoble — the hardest of the 3 ways up

Elevation profile

227 m → 1323 m
0–4% 4–6% 6–8% 8–10% 10–14% 14%+
Steepest kilometre: km 2 at 10.3% — peaks at 14.9%
Elevation inside a tunnel is unreliable — the survey reads the mountain above the road, not the road. Report a tunnel

Climb stats

1096 m Ascent
14.84 km Length
7.39% Average
16% Maximum
1323 m Summit altitude
255 Difficulty

Kilometre by kilometre

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Km Altitude Gain Average Max Gradient
1 300 m +72 m 7.2% 11%
2 402 m +103 m 10.3% 16%
3 481 m +79 m 7.9% 10%
4 571 m +90 m 9% 13%
5 664 m +92 m 9.2% 12%
6 752 m +88 m 8.8% 11%
7 801 m +49 m 4.9% 10%
8 874 m +73 m 7.3% 15%
9 945 m +71 m 7.1% 11%
10 986 m +41 m 4.1% 7%

Route map

Paved Unpaved Cobblestone Unknown
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Photos

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Rider notes

What it is actually like, from people who have ridden it
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How hard is 255?

Difficulty score is length × gradient, weighted for the steepest kilometre.

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Conditions at the summit

13°
Clear · feels like 11°
Wind 4 km/h NE
Updated 3 min ago
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