Durchbruchstal der Warnow und Mildenitz, Nature reserve near Sternberg, Germany

The Durchbruchstal is a protected nature reserve where the Mildenitz River flows into the Warnow River through steep slopes covered with mixed forests. The valley spans about 80 hectares and displays a distinctive geological structure.

The nature reserve was designated on 24 April 1965, protecting one of Mecklenburg-Vorpommern's largest breakthrough valleys and a three-kilometre stretch of the Warnow that has never been altered by water engineering. It lies within the Sternberger Seenland nature park and forms part of the EU Natura 2000 site Warnowtal mit kleinen Zuflüssen.

The reserve lies within the Sternberger Seenland Nature Park, and marked hiking trails lead visitors into the valley. The stream mussel, a protected species, lives in the river system, though it is unclear whether a population still able to reproduce survives there.

Marked hiking trails lead into the reserve, which lies within the Naturpark Sternberger Seenland. The protected area covers 80 hectares around the mouth of the Mildenitz where it joins the Warnow, and the trails are the only way to enter. Nutrient input into the river system is the main pressure on the site.

The area contains one of the largest gorges in Mecklenburg-Vorpommern with a roughly three-kilometer river section that has barely been altered by water engineering projects. This natural river form is rare in the region today.