The remnants of the former gunbastions and fortifications are today transformed into rock gardens with a large collection of alpine and mountain plants. One hill is made of coral limestone from Fakse and displays first of all calciphilous plants. The other hill displays a large collection of plants from the Greek mountains, the Alps, Greenland and the Caucasus mountains. On the lower slopes of the hills and at the foot of the rock gardens the collection comprises acidophilous plants like Rhododendron and a number of rare woody species. In this section old, historical roses are displayed.
Most species have a lovely scent when in flower.