Park in the large Markstein car park at the junction of the Route des Crêtes and the D430 from Guebwiller.
(S/E) Take the road (D430) eastwards for 200m, then head north-west along the path marked first with a blue triangle, then with a red triangle, which leads away from the Markstein site and crosses several ski slopes.
(1) Further on, the path veers off in a north-north-easterly direction.
(2) Passing the Steinlebach farmhouse inn in a landscape typical of the Vosges crests. Continue along the same path which, after passing through a forest,
(3) leads to a large meadow with a multitude of wildflowers.
(4) At the Club Vosgien sign for "Oberlauchen", change course and head due north, taking the small yellow rectangular path that climbs up to the Col d'Oberlauchen. The climb offers superb views of the Markstein site and the Grand Ballon. At the top of the pass, don't hesitate to walk a few extra metres to the north to admire the plunging view over the bottom of the Sondernach valley.
(5) At the top of the pass, take a forest track heading north-west, signposted "chevalet bleu", to a picnic area on the edge of the D27.
(6) Cross the D27 and take the unmarked, signposted Salzbach path directly opposite.
(7) At a crossroads, continue towards Salzbach until you reach the farmhouse inn of the same name. This farmhouse, located outside the usual farmhouse inn circuit, is in an absolutely superb natural setting with panoramic views over the various valleys as far as the Hohneck, and has retained an authenticity that is rare in this day and age. Here you can enjoy a delicious meal or a drink.
(8) Follow the access road to the farm inn for 300 metres until you reach the pedestrian crossroads.
(7) Take a pleasant path, signposted in red and white, which leads to the Fecht (nearby spring) and then to the Col d'Hahnenbrunnen on the Route des Crêtes (D430).
(10) From the pass, take the GR®5, signposted in red and white, southwards for around 2km through stubble fields and pastures until you reach the Route des Crêtes.
(11) Cross the road and follow a large path marked Red and White for around 800 metres, heading South-West, which serves as a "car park" for the paragliders mentioned below.
(12) When this path bends southwards, turn left, due east, via a turnstile at the edge of a cow park, onto a small, fairly steep, unmarked path that leads to the summit of the Trehkopf and serves as an access ramp for the many paragliders. From the top, the view over the Kruth valley and surrounding peaks to the west is quite impressive, which explains why when conditions are favourable, the site is stormed by a multitude of paragliders.
(13) Continue along this path to cross the Trehkopf from west to east. After a slight descent, you'll find a red and white signposted path that takes you back to the Markstein car park (S/E).
Enjoy the hike.