There are only a few medieval towns in Germany that are as rich in history as the Franconian town of Rothenburg ob der Tauber. Located some 420 meters above sea level and overlooking the valley of the Tauber River, its beautiful gates, towers and massive walls present a silhouette that never fails to impress the never-ending flow of visitors. Traces of the first settlement by Celts in about 500 B.C. can be found on the opposite side of the valley, on the Engelsburg castle ruins. Around the year 960, the city of Detwang in the Tauber valley was founded and at the same time a citadel was built on the hill above the Tauber River. The town that developed from the small borough was awarded its charter and declared a Free Imperial City by Emperor Rudolph I in 1274. The following century and a half saw the expansion of the town and its territory into the early 15th century. The first city wall dates as early as the 12th century. The outer town wall with its towers, gates, and battlements dates to the 14th century.