Grüne Hölle

The Grüne Hölle ('Green Hell') is a forested gorge trail near Bollendorf on the Sauer river, straddling the German–Luxembourg border. Route 55 winds through a narrow valley of mossy sandstone rock formations and dense broadleaf woodland that stays remarkably cool even during summer heat — giving the trail its dramatic name. Visitor reviews consistently describe an almost fairytale atmosphere, with very few other hikers even on weekends. A free audio tour is available for download, covering the geology and woodland ecology of the area. Dogs are welcome on the trail.