From Freiburg (B294) or Freiburg-Nord (A5 Karlsruhe-Basel) to Waldkirch, turn left direction Bleibach/Furtwangen (L173). Drive through the Simonswaldertal valley (L173), then a further 18 km past Bleibach when you reach the resort town of Gutenbach in the Black Forest (828 m above SL).
From Town Hall , walk around 100 m in the direction of Freiburg, then take the first right turn. After 50 m, turn sharp right following the sign 'Sportplatz' (Sports ground) until you come to the Catholic church. Pass the church and after 50 m follow the road to the right leading to Hintertal. Walk 500 m, then turn left along the Buhlweg, an unmade trail. The trail leads across a mountain pasture into the forest. Having left the forest, keep following the trail until the first junction. Take a left turn to reach the Lehmannskreuz walkers' car park (map of trails). From there walk to the edge of the forest, go past a barrier and keep following the trail. The trail takes you first along the edge of the forest and then through the forest. You'll then come to a fork. The left trail leads to Lehmannsgrundhof. To reach Hintereck however, just go straight on along the edge of the forest and through the forest again. After 50 m into the forest, the trail makes a sharp left bend leading down to Hintereck. ( The narrow path to the right leads to the Spitzer Stein). Following the left turn down, you'll be in Hintereck within 5 minutes.
NB:
In autumn 1999, Buhlweg and the section of the path between the car park and the turning towards Lehmannsgrundhof will be tarred. The turning for Buhlweg will then be a further 100m away towards Hintertal, just before Schulstrasse runs into Hintertalstrasse.
2nd option:
Similarly to option 1, go to the Catholic church, then straight on up the hill following the sign 'Sports ground'. 30 m past a sharp left bend, the steep path takes a sharp right turn leading up to the sports ground on the Sommerberg. On the top, the path leads you to the right through the Schildeckerwald forest across a broad forester's track. Go down along the edge of the forest to the walkers' car park at Lehmannskreuz. From there follow the directions described in option 1.