The Kemper Werth (also known as auf dem Schänzchen and historically as the Pfaffenmütze) is a promontory in the Rhine at the mouth of the River Sieg, in the northeast of Bonn, in Germany. Formerly a pair of islands, it became attached to the river bank as a result of engineering work altering the confluence of the Sieg. It was the site of a fort during the Eighty Years' War and is now part of a protected natural area, the Naturschutzgebiet Siegaue.