Die Kugelbarke in Cuxhaven, Niedersachsen (Lower Saxony), Northern Germany. Cuxhaven is situated on the shore of the Nordsee at the mouth of the Elbe River. The city and its precursor Ritzebüttel belonged to Hamburg from the 13th century until 1937. The island of Neuwerk, a Hamburg dependency, is located just northwest of Cuxhaven in the North Sea. The city’s symbol, known as the Kugelbake is a beacon once used as a lighthouse; the wooden landmark on the mouth of the Elbe marks the boundary between the river and the North Sea.