Kalkberg

The nearby Chemische Fabrik Kalk, as it was then known, dumped its production residues here. The mound was originally bare, and because its summit was covered in snow in winter, locals called it the "Kalker Alpen" (Kalk Alps). According to the City of Cologne, dumping ended shortly before Germany's first waste act came into force in 1972. The Kalkberg is therefore not subject to waste law or landfill regulations, only to the Soil Protection Ordinance. The later owner, GSE, covered the summit with about 50 cm of clay from 1999 to 2004 so that surface water would not wash potential pollutants into the groundwater.

In the city's architectural guide "Rechtsrheinisches Köln" (Cologne East of the Rhine), the Kalkberg features on all four tours. The guide cites its central position on the right bank of the Rhine and the 360-degree view over all the districts there. In its assessment, connections and proportions are conveyed more impressively from here than from the Kölntriangle, which stands too far out on the edge by the Rhine.

Since a council resolution in 2005, the site has been earmarked as an alternative location close to the city for a rescue helicopter base. Until it is completed, the helicopters are stationed at Cologne Bonn Airport. In 2011, the Administrative Court of Cologne dismissed a lawsuit brought by a local resident, and the Higher Administrative Court rejected her appeal.