Ahr (German pronunciation: [ˈaːɐ̯]) is a river in Germany, a left tributary of the Rhine. Its source is at an elevation of approximately 470 metres (1,540 ft) above sea level in Blankenheim in the Eifel, in the cellar of a timber-frame house near the castle of Blankenheim. After 18 kilometres (11 mi) it crosses from North Rhine-Westphalia into Rhineland-Palatinate. The Ahr flows through Ahr valley or Ahrtal, passing through the towns of Schuld, Altenahr and Bad Neuenahr-Ahrweiler.
https://en.wikipedia.org/wiki/Ahr