On the heights of the Doller and Thur valleys

Drive to the village of Rimbach-près-Masevaux, located in the Masevaux valley (Doller valley).
Arriving from the south, when you reach the church (on your left), park in the car park below on the right.

(S/E) Leave the car park behind you and take the street on the right as you exit the car park to cross the village, heading towards Basse Bers, Lac des Perches (or Sternsee) and Col des Perches.
In the village, at each crossroads (6 until the last houses): take the left-hand road.
Follow the yellow ring (Club Vosgien sign) towards Basse Bers (look carefully at the tree trunks to spot this yellow ring).
The climb up to Basses Bers is quite steep, so take your time.

(1) You will arrive at Basse Bers at a clearing in the middle of which is a refuge belonging to the Scouts and Guides of France. It is regularly occupied. You can recognise it by its red shutters. Take a good look at the façade to the right of the refuge's entrance door, someone is watching you and smiling...
Continue along the path, going around the refuge on the left, towards Lac des Perches (Sternsee) and Col des Perches.
The trail is marked with a red triangle by the Club Vosgien all the way to the lake.
Be aware of the uphill gradient, which requires some effort... Climb without rushing and without stress.

(2) When you reach Lac des Perches, go around it by taking the path on the right, which after a few steps leads to a ford, which you should cross.
Follow the path along the lake (after the ford, it climbs and turns left).
After about 100 metres, take the path climbing to the right, which will lead you to Col des Perches, marked by a Club Vosgien sign: blue rectangle
This is also a fairly steep climb...

(3) At Col des Perches, turn right onto the Grande Randonnée trail (red rectangle,^GR®5), towards Col de Rimbach or Belacker.
Follow the ridge (wooded but with a view of the ridge on the other side of the valley, the Grand Ballon and Markstein, on your left), following the Grande Randonnée trail (red rectangle).

(4) Please note: there is a fork in the path here. Look for and take the path that slopes gently upwards and heads to the right.

(5) At the Col de Rimbach, follow the path until you reach a fork. To the left is a wooden shelter. Continue straight ahead and take the small path opposite, keeping an eye out for the red rectangle pointing towards Belacker.
Follow this path until you reach the stubble fields.
Continue along the path, go through the gate, turn left and head towards the Belacker inn.

(6) Walk along the right-hand side of the farm and head towards Rossberg, following the red rectangle sign. Follow this path.

(7) Pass by Vogelstein while enjoying the view, and continue to the Mulhouse Ski Club refuge.

(8) Follow the path (you will pass a fountain on your right) until you reach the next crossroads with a gate. Do not go through the gate; take the unmarked path on the right, which runs alongside a fence and leads you straight to the summit of Rossberg.

(9) After enjoying the view, take the path to the right of the path you came from.
Descend from Rossberg along another fence until you reach the next path on your left, which crosses the field towards the forest below. This path is marked by a red rectangle with a white stripe.
At the next crossroads, turn right (yellow rectangle) and head towards Fuchsfelsen.
Follow the path for about 400 metres, looking out for a path on the left marked with a yellow disc ("disc" is the term used by the Club Vosgien, not "circle" or "round"), which you will need to take.
From this point, you will descend the mountainside through the woods, but you will be surprised by the magnificent views you will encounter. Take your time and enjoy the scenery, you deserve it.

(10) At Fuchsfelsen, turn right off the path you came on, following the path marked with a red disc. Head towards Duerenfels.
Let yourself be surprised by the views; you are in the forest of volcanoes...

(11) Follow this path (red disc) which takes you through a fairly wild forest of beech and fir trees.
You will come to a large crossroads with a forest path. Take this path on the right (it goes uphill), marked with a blue triangle.
Follow this path (marked with a blue triangle). Be careful, as the path is quite wide and can be tedious to walk along. After about 1 km, the path makes a hairpin turn to the right.

(12) At the bottom of the bend, take the small path in front of you (to the left of the forest path), still marked with a blue triangle.
The path continues to climb for about 1 km before joining a small trail.

(13) Take this path downhill to the left, marked with a red rectangle with a white stripe. Head towards Rimbach.
This path will take you down a remarkably wild and beautiful valley. It will lead you to a new forest track.

(14) Turn right (red rectangle crossed out in white, towards Rimbach).
Follow this path marked with a red rectangle crossed out in white to the village of Rimbach.
You will return to the street you took at the start. Go down it to the left until you reach the car park where you started (S/E).

(1) SGDF Basse Berses refuge: water source (drinkable) convenient for filling up with water and camping.
(2) Lac des Perches: no, you can't swim here, but you can rest and contemplate the wild scenery.
(6) Ferme-Auberge Belacker: you need to book in advance to eat and sleep here (09 88 18 77 74 or 06 30 08 11 26), but you can also stop for a drink and enjoy the view.
(8) Refuge Ski Club Mulhouse: you can eat and sleep in this refuge, provided there is a caretaker on duty (03 89 48 76 77).
(10) Enjoy the panoramic view.

Note: I have described the walk as difficult, given the length in terms of time, distance and the somewhat challenging elevation gain in places. But technically, there is no difficulty: you just have to put one foot in front of the other and so on, while taking care.

Enjoy your hike!

Why Lac des Perches or Sternsee?
These two names refer to the same lake.
"Perches" has nothing to do with fish, as there are no perch in this lake. The lake is named after the Bers (Haute and Basse). Bers is the name of the high stubble fields located not far from the lake. "Perches" is a phonetic approximation of the word "Bers".
Sternsee (Star Lake) comes from a (sad) legend: a boy, lost in the night by the lake, sees stars reflected on the lake. Wanting to reach them, he drowns...
It is said that he was the son of Count Maso (founder of the town of Masevaux, Masovilla at the time), who is believed to have lived in the 8th century.
Count Maso was the nephew of Etichon-Adalric of Alsace (also referred to in texts by the following names: Eticho, Aticus, Attich, Etih, Chadalricus), father of Saint Odile, Duke of Alsace.
Count Maso did indeed lose his son, but the latter is said to have drowned in the Doller (a tributary of the Ill, forming the Masevaux valley).