Olef

The Olef is a river in Liège, Belgium and North Rhine-Westphalia, Germany. It is 27.9 kilometres long and a left-hand tributary of the Urft. It flows through the Eifel Mountains in the western part of the Germany and eastern part of Belgium.

The Olef rises on the Ramscheider Höhe, near the Zitter Forest, about 2.2 km southwest of Hollerath at an elevation of 639 m above sea level , immediately on the state border. From here it flows initially northwest and through the woods of the Dreiherren Wald. The valley of the Olef forms the state border here which runs along the river. From its confluence with the Wiesbach it enters Germany. It then forms inter alia, the eastern boundary of the safety zones of the Elsenborn Military Training Area. The river course changes direction in a wide arc to head east.

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