CLERVAUX (clara vallis), a town in the northern province of Oesling, grand-duchy of Luxembourg, on the Clerf, a tributary of the Sure. Pop. (1927) 1,680. The old castle of the Lannoy family still exists. In 1798 the people of Clervaux specially dis tinguished themselves against the French establishment of con scription. The survivors of this Kloppel-krieg ("cudgel war") were shot, and a fine monument commemorates them.