Eifel (Īˈfəl) [key], undulating plateau, W Germany, N of the Moselle River and E of the Ardennes. The Eifel forms the northwestern part of the Rhenish Slate Mts. and is a barren area characterized by deep valleys, extinct volcanoes, and crater lakes; it is a tourist attraction. The highest point (2,447 ft/746 m) is the Hohe Acht. Iron and lead deposits, now exhausted, were mined there in the late 19th cent. Since 1870 many area residents have moved to the Ruhr and Aachen.