Ernster (Luxembourgish: Iernster) is a small town in the commune of Niederanven, in central Luxembourg. As of 2005, the town has a population of 346.
ERNSTER is also the name of a bookshop.
Coordinates: 49°41′N 6°15′E / 49.683°N 6.25°E / 49.683; 6.25