All you need to know about Etang De La Gruère. The “Étang de la Gruère” is the largest moor lake of Switzerland and the perfect place for a hike around the Swiss Lake or doing a picnic and observing nature.

Text and Pictures by Marc Gottwald

The nature of Etang de la Gruère

Welcome to the Étang de la Gruère”, a tiny lake in the canton of Jura, Switzerland. Honestly, a pretty long name for such a small Swiss lake. And yes, it may be small in comparison with other Swiss lakes (Lake Neuchâtel: 21830ha) at 8ha, but it is the largest moor lake of Switzerland.

But trust me, this region is something very special. A place where you feel like you are in the middle of the wilderness.

The lake is found in the Jura range in the middle of Saignelégier and Tramelan. Furthermore, the Etang de la Gruere elevates at around 1000 meters above sea level and measures 600 meters in the length, 60m in the width, and is 5m deep. And honestly, the nature looks so perfect, that we could think that this is a natural lake. But that’s wrong.

Formed by a dam

The moor lake was formed in the 17th century during the construction of an artificial dam for a mill to generate water power. Nevertheless, nature is of such great importance that today there is a nature reserve with the forest and the lake. Therefore, it is also not allowed to leave the paths.

It is interesting to note that the Étang de la Gruère has a calcareous subsoil. Normally, it would be porous and the water would immediately run off through hollows. But how can the lake exist after all?

The glaciers retreated about 13000 years ago. Due to their enormous weight, they have flattened the former porous ground. Over time, many sediments such as clay and marl have been brought in. This means that the water could no longer drain away properly. The result was a peat bog. Then in the 17th century came the artificial dam, which turned the moor slowly into a lake.

That’s also the reason why the Etang de la Gruère has brown colored water. In Les Cerlatez there is a nature conservation centre where you can learn a lot about the moor. Let us now look at the 5 Top activities to do at Étang de la Gruère in the canton of Jura.

1). Hiking

The lake features a well-designed hiking trail for hikers. It starts from Moulin De la Gruère and goes around the Etang de la Gruère. It’s a special experience walking on the former moor soil on the lake trail, crossing the bridges and wooden boardwalks. The hike offers a wonderful scenery by following the signs posts.

Furthermore, there is a lot of flora and fauna in the region to discover and observe. Because peatlands are some of the areas with the greatest biodiversity. The hike is ideal for everyone as it’s very flat, so also for elderly, children, and dogs. And honestly, it’s more a walk than a hike as the circular walk takes only around 50 minutes. You can’t find that on the hiking maps, however, you can easily follow along the lake.

If you want to do a bigger hike in this region you can also start in Saignélegier hike to another beautiful but less known lake, the “Etang des Royes”. Then you continue to the “Étang de la Gruère” and hike afterwards through the stunning moorlands of “La Tourbière”. You will definitively feel like in another world as it’s something totally different from what we normally know here in Switzerland! In the end, the hike will finish in “La-Chaux-de-Brelaux” where a train is waiting for you every hour. The hike is taking around 3 hours and 30 minutes and is very flat.

2). Enjoy a picnic at Étang de la Gruère

The moor lake offers very beautiful picnic spots as you walk along the paths with several benches. During the weekends and in the summer holidays you might see a lot of people.

However, during the week you can enjoy the silence, recharge batteries and have views over the beautiful lake and the landscapes full of fir trees. Sometimes a man even plays his alphorn. What could be better?

Please make sure you take all the trash with you at home. This is because I haven’t seen any trash bins since my last visit. Furthermore, the nature reserve area does not allow any form of fire.

3). Watch animals and birds

The region has many animal and plant species. Because the moorland has very few nutrients, plant species can grow and animal species can live here that have no chance in nutrient-rich agricultural meadows because of the faster-growing competition. Some of them include butterflies, dragonflies, and beetles.

4). Swimming

The Etang de la Gruère is a perfect place for outdoor swimming in summer. The few spots for swimming are marked and distributed around the lake. You can enjoy a swim in this beautiful Swiss lake or sunbathe at the shores and observe the surrounding nature. A very special experience!  

5). Ice skate

The lake freezes during the winter seasons. It gives a rare experience in this winter wonderland. To ice skate is always on your own danger as there are no signs if the ice is already good for ice skating or not. It feels special to skate on nature-made ice that is surrounded by beautiful views. Beginners, intermediate and experienced skaters have great moments to enjoy on the ice. Lastly, the activity depends on the weather. It is not possible if there is no cold weather for an amount of time or if the lake is snow covered. Check the weather, temperature, and ice before you start this activity.

How to reach the Étang de la Gruère

There are several ways to get to the “Étang de la Gruère”: by public transportation with train and bus or by car. If you go by train or bus it’s a very beautiful journey through the Jura Highlands which I can really recommend, however, please make sure to check the timetable as especially the buses are driving unregularly. Of course, you can also do a hike from Saignélegier, then you are more independent. The place is very close from La-Chaux-de-Fonds and can be easily combined.

Final thoughts Étang de la Gruère

Étang De La Gruère is ranked as the largest moor lake in Switzerland. The beautiful Swiss Lake is situated among the trees and provides great activities like hiking, swimming, picnics and sometimes even ice skating in winter. Furthermore, it is worth watching sunrise and sunset. If you come by car, you will find two parking lots. A great place to visit if you are in the Jura region.