The High Fens Nature Park on the Belgian side extends into the German-speaking Community of Belgium in the province of Liège and, together with the German part, forms the cross-border High Fens-Eifel Nature Park. The area is one of the largest raised bogs in Europe and was formed approximately 7,500 years ago at the end of the last Ice Age. Its characteristic features are its vast moorland areas with pools, gnarled birch trees, spruce trees, and heathlands, creating a mystical atmosphere, especially in foggy weather.
The park offers numerous hiking trails, including the Sentier de la Trientale, which leads through the Sourbrodter Venn and passes historical sites such as the Russian Cross. The trails are mostly on wooden boardwalks or marked paths to protect the fragile moorland landscape. The daffodil bloom is particularly worth seeing in spring, when parts of the Fens are bathed in a sea of yellow blossoms.