Rheinland Nature Park is a nature park in North Rhine-Westphalia, situated between Bergheim, Kerpen, Erftstadt, Euskirchen, Königswinter, Bornheim, Bonn, Brühl, Hürth, Frechen and Pulheim. It covers an area of about 880 km². From Wikipedia
Activities include geological walks, star-gazing, accessibility-focused programs, and the Eifel National Park's broom blossom festival.