Aar

The Aar is a 50-kilometre-long river in western Germany, left tributary of the Lahn. It rises in the Taunus mountains, near Taunusstein. It flows generally north through the towns Taunusstein, Bad Schwalbach, Aarbergen and Hahnstätten. It flows into the Lahn in Diez.

The name Aar is a common name of rivers and brooks in German-speaking Central Europe, as exemplified by the similarly named tributary to the same Lahn river Aar . The pre-German word Aar means "quick-flowing water", in a metaphorical sense "small river in a space between mountains". It is commonly conserved in southern German-speaking areas in settlement names ending with -ach.

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