Schledden like the Westerschledde are a geological peculiarity of the Haarstranges. Due to the karstified subsoil, dry valleys have formed here, which only carry water above ground in winter or after heavy rainfall.
The Westerschledde begins behind Langenstraße (Rüthen), north of the "Spitzen Warte" and flows into the Störmeder Bach after 15.3 km of running.
The nature reserve is about 365 hectares large and impresses with the special characteristics of a historically grown cultural landscape. The shaping power of flowing water and human cultivation, especially centuries of grazing, have created a wild and romantic valley.
The oak and Buchenwald forests in the south still contain a rich herb layer in places and are the habitat of rare animal species. The calcareous grasslands in the central part of the area are relics of former extensive grazing. This vegetation type is one of the most species-rich communities in Central Europe. The open valley areas are the habitat of numerous dragonflies, butterflies and bird species.
The shallow calcareous shear soils are home to highly endangered arable wild herbs. To protect them, marginal strips have been created where no fertilizer or herbicides are used.
Local authorities and conservationists try to preserve the open character of the Westerschledde valley through targeted maintenance measures and sheep grazing.