The socalled "Spoliensäule" (literally "column of spoils"), which is the gateway to the St. Martin's Square, displays fragments of architecture from six centuries of civic history. The pedestal consists of a wreath of 10 reproductions of old boundary stones.
The special charme of the square is due to the 18th and 19th century buildings, the fountain and the old trees.
At one side of this beautiful square with its two shady chestnut trees there once stood the "Kaufhaus”, which was used, among other things, for storing the city’s grain reserves. Also to be seen here are the Old City Hall of 1745, now the home of the municipal music school, the House of the Family Rettig, from the middle of the 18th century, and the former Hotel Zum Donnersberg, where Napoleon himself once breakfasted.