Cascade de la Diomaz

Cascade de la Diomaz is a waterfall tucked into the forested slopes above Mégevette, a small commune in the Chablais area of the Haute-Savoie department in eastern France. It forms where the Diomaz stream, a tributary of the river Brevon that rises within Mégevette itself, tumbles over a series of rocky steps hidden among the trees. Rather than a single drop, the site is really a sequence of smaller falls that together give the impression of water cascading continuously down the hillside.

Where exactly is the waterfall located?

The falls sit close to the neighbouring commune of Bellevaux, inside a valley known locally as the Val d'Enfer. This is classic foothill country for the Chablais Alps: narrow, wooded valleys cut by streams draining down from the higher ridges. Mégevette itself is a quiet mountain village that serves mainly as the starting point for hikers heading toward the waterfall and the surrounding hills.

What makes this waterfall distinctive?

At the base of the falls, the water has carved a series of natural rock basins known locally as the "marmites des Chartreux," or Chartreux pools — a name recalling the Carthusian monks once associated with the area. The connection is reinforced by a small cross cut directly into one of the streamside rocks at the foot of the cascade, referred to as the Croix des Chartreux. That detail gives the spot a layer of local history alongside its natural scenery, something not every waterfall in the region can claim.

How do you get there, and what is the trail like?

The most common approach starts at the Saint-Bruno chapel in the Val d'Enfer valley. From there, the round-trip walk covers roughly five kilometres and takes about two hours for an average walker, with a moderate amount of elevation gain along the way. Several stream crossings are part of the route, so sturdy, ideally water-resistant hiking shoes are worth bringing. An alternative approach begins at Lac du Vallon, from where a forest path leads past a number of smaller cascades before reaching the main falls.

Is the hike suitable for families?

The walk is generally considered family-friendly, though the stream fords and occasionally uneven ground mean it is not a casual stroll for anyone in unsuitable footwear. Extra care is needed near the falls themselves, where wet rock can be slippery, particularly for children or less confident walkers.

Can you do anything besides hiking here?

The Diomaz stream is also known among canyoning enthusiasts. Its stepped course and natural pools make a section of the valley suitable for canyon descents, typically organised through guided outfits rather than attempted independently. That makes the site a draw for visitors looking for something more active than a straightforward walk to a viewpoint.

Frequently asked questions

What stream forms the waterfall? The falls are formed by the Diomaz stream, a tributary of the river Brevon that originates within the commune of Mégevette.

How long does the hike take? Starting from the Saint-Bruno chapel in the Val d'Enfer valley, the round trip covers about five kilometres and takes roughly two hours.

Is the trail difficult? The climb is moderate, but the route crosses the stream several times, so water-resistant hiking shoes are recommended.

Where does the name "marmites des Chartreux" come from? It refers to the Carthusian monks once linked to the area, also commemorated by a cross carved into a rock at the base of the falls.

Can you go canyoning near the waterfall? Yes, the Diomaz valley is used for canyon descents, usually run by guided operators rather than as a solo activity.

What is the nearest larger village? Bellevaux, which borders Mégevette in the Chablais area, is the nearest larger settlement.