The island park, whose southern boundary had previously been the Eselsbach stream, was extended to the south at the end of the 19th century through afforestation. At the beginning of the 20th century, the plantings gave rise to a forest park with extensive meadows and a new pond, which was made accessible by winding park paths. It increasingly formed a natural unit with the former island park. In 1938, the city of Düsseldorf acquired the entire estate, and the park has been open to the public since 1950. The network of paths in the forest park was extended and a spacious children's playground was created. The park was given a landscaped, square-like main entrance on Deutzer Straße. The design of the older island park by the palace building has remained virtually unchanged.