The Ain department is not a cycling destination in the way that Savoie or the Hautes-Alpes are cycling destinations. It does not have the Alpe d'Huez brand or the Galibier mythology. What it has is the Grand Colombier.
At 1,501 metres, the Grand Colombier is not a high mountain. It is not even technically in the Alps — it rises from the Bugey plateau, the limestone hill country that separates the Rhône valley from the Jura. But gradient is not the same thing as altitude, and the Grand Colombier's slopes make this distinction felt. The approach that the Tour Auvergne-Rhône-Alpes uses today measures 8.4 kilometres at an average of 10.2 percent. That average reflects a consistent brutality across its entire length. There are no rest sections. There are no flat intermediates where riders reset. There is just the climb.
The Tour de France has included the Grand Colombier in multiple editions. Riders who have been over it do not describe it as a beautiful mountain. They describe it as a hard one.
The Approaches
The Grand Colombier can be approached from four directions. Each produces a different experience.
The Culoz approach (north face): This is the most famous approach and the one associated with Tour de France history. Culoz is a small town on the Rhône's east bank, north of Belley, and the climb from there ascends the north face of the summit. Distance and gradient vary depending on which source you use, but expect approximately 8–9 kilometres of consistent climbing gaining around 900 metres from the valley floor. The upper section features the Lacets du Grand Colombier — a series of tight hairpins visible from the valley below that appear on every helicopter shot of races that tackle this face. The hairpins are not the hardest section; they are simply the most photogenic. The gradient is persistent throughout.
The stage-7 approach (south/southeast face): Today's race uses the steep southern approach, confirmed at 8.4km and 10.2% average. This is a more direct assault on the summit with fewer hairpins and more sustained straight-line gradient. From the Ain valley floor near Artemare, the road climbs through forest before emerging onto the upper limestone plateau. This is the approach that produces the highest average gradient of any published route to the summit.
The Anglefort approach (west face): The shortest and steepest option. Approximately 4–5 kilometres from the Rhône valley near Anglefort, with sections that push well above 15 percent. This is not a training climb; it is an interval with context. Use it when you have already climbed everything else.
The Champagne-en-Valromey approach (southwest): The longest approach, starting from the Valserine valley and ascending through the Valromey plateau. Roughly 14 kilometres at a more moderate average gradient. Used for long sustained base work rather than racing-speed testing.
The Multi-Approach Loop
The standard visiting cyclist's loop uses two approaches in a single day: climb the Culoz face for the hairpins and Tour de France context, descend to the south, climb back up the southern approach for the harder sustained gradient experience, and descend the Champagne valley for a long, scenic finishing roll. The loop covers approximately 70–80 kilometres with 2,000–2,200 metres of climbing depending on the exact start point.
Start in Belley. The prefectural town of the Ain's Bugey canton is 15 minutes by car from both the Culoz and Artemare base areas, has accommodation, cafés, and the logistical infrastructure for a day's ride. Leave Belley toward Culoz in the morning, climb the north face, descend to the south side, return up the stage-7 approach, and roll back through the Valromey or via Bellegarde-sur-Valserine. The route is well-signed; the roads are quiet by Alpine standards.
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Join ZealZagFollow us on InstagramWhat the Climb Feels Like
The Grand Colombier's gradient does not hide itself. From the base, the slope ahead is immediately visible as something that will cost effort. There is no gradual increase, no false assurance that the opening kilometres are easy — the climb is at gradient from the start.
The Culoz hairpins are the climb's best-known visual element, but they are not where riders struggle most. The upper section, above the last hairpin and onto the more exposed limestone plateau, is where the wind arrives and the gradient sustains. The final kilometre to the summit is open, exposed to whatever weather the Jura is producing, and unambiguously hard.
In wet conditions — as today's race demonstrates — the technical challenge changes. The smooth limestone sections in the upper third can lose traction. The forest sections hold moisture. The approach that the race uses today, at 10.2 percent in the rain, is a fundamentally different test from the dry training ride.
When to Ride
April through October. The Bugey plateau is significantly lower than the Savoie and Isère passes, meaning the Grand Colombier is accessible earlier in spring and later in autumn than many comparable French climbs. Snow closes the summit road during winter but rarely persists past early March.
May and June are optimal: temperatures in the high teens, limited traffic outside race weekends, and the plateau vegetation at its best before the summer heat dries the fields. September is excellent: quiet roads, crisp descents, stable weather.
July and August: The Ain plateau gets hot. Riding before 09:00 is the practical solution. The mountain itself stays cooler above 1,000 metres, but the valley approaches through Culoz and Artemare absorb Rhône-valley heat in July afternoons.
Getting There
From Lyon: 1.5 hours by car east on the A42/A40 toward Geneva, turning south at Bellegarde-sur-Valserine toward Belley. Train options are less direct but feasible via the Lyon–Geneva line with a connection.
From Geneva: 1.5 hours south by car through Bellegarde. Swiss border is 30 minutes north of Belley.
From Chambéry: 50 minutes west through Yenne to Belley. The Lac du Bourget's western shore road (D914) runs directly north from Chambéry toward Culoz — a scenic approach that adds the lake to the day.
Where to Base
Belley is the practical base. The historic town is the Ain Bugey's capital — a proper market town with hotels, restaurants, and a Saturday market that supplies excellent Bugey cheese and local wine. The Bugey appellation covers the AOC wines produced in these hills; the Cerdon rosé (a gently sparkling natural-method wine) is a local speciality worth finding.
Culoz is smaller and closer to the north face base. Basic accommodation; functional for a single-climb visit. The train station on the Lyon–Geneva line makes it accessible by rail if arriving without a car.
Artemare (south side base) has limited accommodation. Practical for reaching the steep southern face first thing in the morning, but most cyclists base in Belley and drive to either start.
Frequently Asked
Is the Grand Colombier suitable as a first major climb? The gradient makes it inappropriate as a first serious climb. Riders comfortable on 5–6 percent passes can be surprised by 10 percent sustained gradients. Approach it having already ridden climbs with double-digit sections elsewhere.
How does it compare to Tour de France climbs? It is harder than most medium-category Tour climbs and comparable to many category-one ascents. The gradient, not the altitude, is the relevant measure. The Grand Colombier at 10.2% is harder than the Col de la Croix de Fer at 5.2%, regardless of altitude difference.
Can I combine the Grand Colombier with rides at the Savoie lakes? Yes. Lac du Bourget (Chambéry) and Lac d'Annecy are both within 60–90 minutes. A multi-day circuit combining the Colombier with the Col du Chat (above Lac du Bourget) and the Semnoz (above Annecy) is one of the most underrated cycling loops in this corner of France.
Where can I find training partners for Ain cycling? Connect with riders in the Bugey and Belley area via Find Athletes in Ain/Belley on ZealZag.
For today's Stage 7 race coverage and GC analysis, see our Stage 7 field report. For yesterday's Stage 6 Crest-Voland coverage, see our Stage 6 field report.