die Düne
dune
A hill of sand piled up by the wind, typically found on coasts or in deserts.
Wir sind barfuß über die hohen Dünen zum Strand gelaufen.
We walked barefoot over the high dunes to the beach.

dune
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dune
A hill of sand piled up by the wind, typically found on coasts or in deserts.
Wir sind barfuß über die hohen Dünen zum Strand gelaufen.
We walked barefoot over the high dunes to the beach.

With places like 'Düne' (dune), the correct preposition is important. Movement up onto the hill is expressed with 'auf die Düne' (onto the dune, accusative). If you are already there, it is 'auf der Düne' (on the dune, dative).
Die Kinder rannten auf die höchste Düne.
The children ran onto the highest dune.
'Düne' (dune) is often combined with verbs of movement or staying in a place. Typical phrases are 'durch die Dünen wandern' (to hike through the dunes), 'in den Dünen spazieren gehen' (to go for a walk in the dunes), or 'auf einer Düne sitzen' (to sit on a dune).
Im Urlaub sind wir jeden Tag durch die Dünen gewandert.
On vacation, we hiked through the dunes every day.
The word 'Düne' (dune) is a common component of compound nouns that describe landscapes. Examples include 'die Sanddüne' (sand dune), 'die Wanderdüne' (shifting dune), and 'die Dünenlandschaft' (dune landscape).
Die Küste ist für ihre beeindruckende Dünenlandschaft bekannt.
The coast is known for its impressive dune landscape.
hill
'der Hügel' and 'die Düne' both describe a rise in the landscape. 'Hügel' is the more general word: it can be made of earth, grass, or stone and appears in many kinds of landscapes. 'Düne' is more specific: it is a hill of sand formed by the wind, especially by the sea or in the desert. The words can be confused because a 'Düne' looks like a 'Hügel'. If only the shape is important, 'Hügel' may fit. If it is about sand, the coast, or the desert, 'Düne' is more precise.

Im Urlaub sind wir früh auf die Düne gestiegen und haben das Meer gesehen.
On vacation, we climbed the dune early and saw the sea.
Am Ende des Weges steht ein kleiner Hügel mit einer Bank darauf.
At the end of the path there is a small hill with a bench on it.