 In Germany, the Holy Roman Emperors built a number of residences, fortified, but essentially palaces rather than castles, at strategic points and on trade routes.The Imperial Palace of Goslar (heavily restored in the 19th century) was built in the early 11th century by Otto III and Henry III, while the ruined Palace at Gelnhausen was received by Frederick Barbarossa prior to 1170.The movement of people and armies also brought about the building of bridges, some of which have survived, including the 12th-century bridge at Besalú, Catalonia, the 11th-century Puente de la Reina, Navarre and the Pont-Saint-Bénézet, Avignon.