 It is surrounded by a city wall from the 16th century.Get in addition to wall sections five of the original 14 towers and the Untertor as one of the former four city gates.The Protestant church of Our Lady (Unserer lieben Frauen)(Johann Gerhard in 1606 became general superintendent of the duchy for 9 years), on the west side of the square dates from the period 1502–1537, the tower is older.