Irreler Waterfalls

The Irrel Waterfalls are the rapids in the lower reach of the Prüm between Prümzurlay and Irrel in the Eifel district of Bitburg-Prüm in Rhineland-Palatinate.
Between Prümzurlay and Irrel, the Prüm has deeply carved itself into the Ferschweiler Plateau, formed by morphologically hard Luxembourg sandstone. The high cliffs of the resulting gorge-like valley are formed by this highly fractured sandstone. The lower slopes are made up of the clays, marls, and gypsums of the Keuper. During the last Ice Age, the slope became unstable, leading to a rockfall. The landslide and avalanche debris consisting of large blocks of Luxembourg sandstone and easily deformable Keuper marls and clays initially dammed up the Prüm. Since the overflow of the reservoir, the more easily removable clays have largely been transported away, leaving only the hard rock fragments behind. While they still obstruct the Prüm's path today, they now only cause low gradient levels that hardly qualify as a waterfall.

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