Gorges du Sierroz: a day trip worth the drive

The Gorges du Sierroz are not on Lake Annecy. Give it thirty-five minutes on the motorway, heading towards Aix-les-Bains: you cross into a different lake basin — Lac du Bourget, not ours — and a different French département, from Haute-Savoie into Savoie. We drove out on a Saturday in July and it was worth the trip. Here is why, and what to know before you go.

Thirty-five minutes, a different lake

The Sierroz is a small river that runs down from the Bauges massif and flows into Lac du Bourget at Grésy-sur-Aix, just north of Aix-les-Bains. From Annecy, take the motorway north to the Aix-Nord exit, two minutes from the site. Geographically it has nothing to do with Lake Annecy: a different valley, different terrain, a river that has never fed our lake. Worth spelling out, because a road map makes this look like a quick lakeside outing — it is not.

Eight hundred metres above the water

The visit runs along suspended walkways built during the site’s renovation: in places you are walking twenty metres above the Sierroz as it works its way between the boulders below. The path crosses the river on a footbridge at a spot called the saut du marchand — “the merchant’s leap” — where smugglers once tried to cross the gorge to dodge customs officers. The name survives on the signage; not much else does.

The walk itself is short with no real climb, and the main path is fully surfaced: accessible by pushchair and self-propelled wheelchair, which is not something you find on every gorge trail.

What you see: mills, a sawmill, and a stone placed in 1813

For centuries this was an industrial site: a mill, a sawmill and an oil press worked the confluence of two streams here, before the whole gorge closed in 1980. The restoration turned those ruins into a proper visit — the Cour des Moulins — with tiered viewing platforms built to take in both the industrial remains and the Grésy waterfall, still the high point of the walk.

A little further along, a stone marks the drowning of Baroness Adèle de Broc, a childhood friend of Queen Hortense, who died here on 10 June 1813 in front of her. The queen had a memorial stele put up warning visitors to take care — the inscription is still there. The story fed the site’s romantic reputation through the nineteenth century, enough that Napoleon III and Empress Eugénie stopped here in 1860.

We do not have photographs of the site itself yet — the cover image on this page is a Savoie landscape, not the gorge — and we will update it once we have images of the walkways and the waterfall.

Practical information

The site reopened on 24 July 2021, after more than forty years closed. Access is free, open every day of the year, with no set hours. Free parking is available on the route des Bauges in Grésy-sur-Aix, right at the start of the trail. Allow one to one and a half hours for the full round trip if you stop at the viewpoints, less if you walk straight through.

The renovation was not a small undertaking: the Auvergne-Rhône-Alpes region put in around €1 million and the Savoie department added €250,000 to fund the walkways, the footbridge and the new exhibition space built above the old visitor building. It shows in the finish — this is not a rope-and-plank trail through a ruin, it is a properly engineered walkway system, which is part of why it can take pushchairs and wheelchairs where most gorge sites cannot.

What we would not do

Treat this as a Lake Annecy outing — it is not one, and visitors who arrive expecting that comparison tend to leave disappointed. Lean over the edge after recent rain: the stone is slippery, which is exactly what the 1813 stele is warning you about. And mix up the Sierroz with a stream that feeds Lake Annecy while planning the route — double-check you are heading towards Aix-les-Bains, not the western shore.

Thirty-five minutes for suspended walkways over a listed gorge, a waterfall and a piece of nineteenth-century history you will not find anywhere near Annecy itself: it is not the lake, but it stands on its own.