Oisans mountain passes · Cycling
Col de la Croix de Fer
A giant of La Marmotte, between Le Rivier-d'Allemont and the Lac de Grand-Maison.
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Profile of the climb — Allemont (Oisans)
Calculated from our GPX track (IGN altitude). Segments coloured according to the gradient.
Gradient kilometre by kilometre view details
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Cycling up the Col de la Croix de Fer from Allemont
To climb Col de la Croix de Fer by bike since Allemont, in the Oisans region (a few kilometres from Bourg-d’Oisans), is one of the must-do climbs in the area: 26.6 km and 1,426 m of elevation gain up to the summit at 2,067 m. After Le Verney, the road climbs steeply at a gradient of 8–10 % for nearly 5 km through the forest. The stretch through Le Rivier-d’Allemont offers a breather, followed by a short descent — care, road sometimes wet. The last part runs alongside the Grand-Maison Reservoir all the way to the top, from where one drops down towards the Col du Glandon, at 2.5 km.
Difficulty: what to expect
Classified Unclassified, the col has a moderate average gradient (4,6 %) who deceives: she is degraded by two runs climbing. The real difficulty lies in the sections close to 12 % and to the length. A flexible gear ratio (34×28 or higher) is recommended. Best period: from June to September, once the mountain pass has been cleared of snow.
A giant of the Tour de France and La Marmotte
The Col de la Croix de Fer regularly features on the route of the Tour de France and of the Critérium du Dauphiné. It is above all a pillar of the legendary cyclosportive The Marmotte, which links the Croix de Fer, the Télégraphe, the Galibier and Alpe d’Huez starting from Bourg-d’Oisans.
Cycling in the Oisans: a unique playground
Bourg-d'Oisans and its valley are the base camp Dream ride for tackling major mountain passes: Alpe d’Huez, Col du Glandon, Col du Galibier and the Croix de Fer are all accessible within a day. You'll find numerous bike rental shops and cyclist-friendly accommodation there.
Frequently asked questions
What is the length of the Col de la Croix de Fer climb by bike?
From Allemont, the climb measures 26.6 km for 1,426 m of elevation gain, at an average gradient of 4.6 %.
Is the Col de la Croix de Fer difficult by bike?
Yes, it is classified as ‘Hors Catégorie’. The average gradient appears gentle, but it is brought down by two descents; the steepest 100 metres are close to 12 %.
What is the altitude of the pass?
The peak reaches a height of 2,067 m. From Allemont, the total elevation gain is 1,426 m.
Can we follow on with the Col du Glandon?
Yes: the Col du Glandon is only 2.5 km from the top of the Croix de Fer.
Neighbouring Cols — Grandes Rousses & Maurienne
Route © OpenStreetMap contributors · Altitude © IGN RGE ALTI · Max gradient over 100 m : climbfinder.