The granite pillar embedded on the summit of the 226 m high Rückenberg served as a first-order station for triangulation for the European degree measurement. The Royal Prussian State Survey recorded the Märkisch Silesian triangular chain in the period from 1868 to 1872 and thus connected the triangular networks of the Kingdom of Saxony (Royal Saxon Triangulation) and the coastal survey with the Berlin base.
The Rückenberg station was number 23 in the Märkisch-Silesian triangle chain and from this station the summits of Brandberg, Hochstein, Gröditzberg, Dalkau, Meiseberg and Hutberg were targeted for the survey. Especially when connecting to the Saxon network, one benefited from the highly precise triangulation between Keulenberg, Strauch and Collm. The Märkisch Silesian triangular group has a connection to the Saxon triangular network in the south as well as a connection to the Thuringian Saxon in the west and to the Silesian triangular group in the east. In the north there is a connection to the Berlin line and the Elbe chain. The granite pillar is certainly not as impressive as the pillars with the inscriptions that give it its name, but it served the same purpose and had to be brought up the mountain in the 19th century. The Rückenberg is the highest mountain on the eastern flank of the Muskau Arch (de.wikipedia.org/wiki/Muskauer_Faltenbogen) There are 3 towers on the summit, a fire watchtower for early detection of forest fires (not open to the public), the ruins of the Bismarck Tower and the observation tower from which you can at least has a beautiful view of the south of the country (Königshainer Berge, Landeskrone, Gröditzberg) The three highest peaks of the western flank of the fold arch are also clearly visible and the geological form of the horseshoe-shaped push end moraine.