East of Réunion Island

The Grand Étang lake loop and the Bras d'Annette falls

Moderate

Distance7.2km

Ascent80m

Estimated time1 h 40

Loop509 – 546 m−80 m of descentStart Parking Grand Étang

Mountain lake
Waterfalls
Easy
Family friendly
National Park core
World Heritage

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Grand Étang is the largest natural mountain freshwater lake in La Réunion, at 525 m in the heights of Saint-Benoît. An eruption made it: the Puy de l'Étang, a volcanic cone less than 3,800 years old, dammed the valley, and its lava flowed all the way down to the sea, where Saint-Benoît stands today. This easy 7.2 km loop, with 80 m of ascent, goes round the lake and on to the Bras d'Annette falls that feed it. Allow 1 h 40 of walking.

Map and profile

Hover over the profile or the trace: the marker follows on both.

Loop, 7.2 km · +80 m / −80 mStops: markers on the trace and on the profile

Stops

Parking Grand ÉtangCar parkkm 0.0 511 m
Cascades Bras d'AnnetteWaterfallkm 3.3 567 m
Point de vue Grand ÉtangViewpointkm 6.0 524 m

In pictures

Trail statusClosed trail nearby: Sentier équestre de Grand Étang

The route crosses it without following it: at the junction, do not take that way.

See the closure →Checked on 7 October 2026 · ONF orders

The route

On the RN3, the road across the Plaines, a "Grand Étang" sign in the heights of Saint-Benoît points to a narrow concrete lane that crosses the sugar cane fields for almost 3 km. The car park is at its end, free, with picnic shelters that fill up at weekends. Hikers reported break-ins there in 2026: leave nothing in sight.

A stony track first climbs the flank of the Puy de l'Étang, then drops back towards the water. On the way, a five-minute detour to the right leads to the viewpoint on top of the Puy, with a bench facing the lake. It is not counted in the distance. At the lake, the path goes round the water at the foot of the wooded ramparts. On the north shore and along the ravine grows one of the last lowland native forests, the "bois de couleurs des Bas", of which only 1 to 2% is left in La Réunion. The banks also hold the island's largest stand of a rare native fern, Cyclosorus interruptus, which trampling threatens: stay on the path.

At the far end of the lake, a fifteen-minute path with two short climbs and a few high steps leads to the Bras d'Annette falls. They come down from the First and Second Bras d'Annette and feed the lake all year. In winter the stream dries up on the surface, but water keeps arriving underground, and the lake has no visible outlet: it only loses water through evaporation and seepage. The rock slabs and pools are slippery. The way back follows the other shore to the starting track.

To the north, a bridle path runs alongside the track. It is closed because it is damaged, but it only touches the loop at its two ends: the loop itself stays open.

Good to know

The lake changes from one season to the next. It can go from almost dry to some ten metres deep in a short time. It is usually highest between March and May and lowest in October and November. After the heavy rain of the southern summer, it often floods the path, and the loop can no longer be walked. There is no drinking water and no toilet at the start, and clouds and rain often arrive around midday in the east: set off early, around 8 am. Before you leave, RandoMafate shows the ONF trail closures and the forecast for the hike. On the way, it keeps the map offline, and your close ones follow your outing on a simple web page.

Plan this hike in RandoMafate

The trail map offline, elevation to the metre, ONF closures and the weather for the day, and the people close to you told when you set off and when you are back.

Frequently asked questions

How long does the Grand Étang loop take?

Allow 1 h 40 of walking for the 7.2 km loop with the Bras d'Annette falls, without breaks. The National Park gives 2 hours. The walk round the lake alone takes about an hour.

Can you do it with children?

Yes. The loop is easy and almost flat, but the ground is stony, and the detour to the falls is harder, with high steps. After rain, the shore turns muddy and slippery.

When does Grand Étang flood?

In the rainy season, the southern summer. The level is usually highest between March and May. When the lake overflows, water covers the path and the loop can no longer be walked. It is lowest in October and November, and it sometimes dries up completely, as in 2007 and 2024.

Can you swim in Grand Étang?

There is no supervised or designated bathing area. In 2026 the regional health agency (ARS) reported a rise in leptospirosis, notably in Saint-Benoît, and freshwater leisure is one of the known exposures: keep out of the water with a cut, and never drink water from the lake or the streams.

Can you get there by bus?

Car Jaune line S2, between Saint-Benoît and Saint-Pierre across the Plaines, stops at the Grand Étang turn-off on the RN3. From there it is almost 3 km on foot up the concrete lane to the car park.