gorges du loup or wolfsschlucht on the mullerthal trail near echternach in luxembourg, canyon with sandstone rocks

aesbech ardennes autumn basalt berdorf canyon cave den echternach erosion europe forest formation geology gorges green hiking hohllay hole huel landscape lee loup luxembourg luxembourgish moss mountain mullerthal natural nature outdoors path perekop rock rocks sandstone stone summer swiss switzerland toursim trail travel tree trees valley wall wolfschlucht wolfsschlucht wood woodland