is a protected nature reserve in the vicinity of the Belgian city of Aalst.
The nature reserve Het Osbroek is situated between Aalst and Erembodegem. The northern part was occupied by the construction of the city park and the urban sports grounds of Aalst. The remaining part is located between the industrial area on the Dender and the residential areas on the Ostend-Brussels motorway. The nature reserve is a European recognized Natura 2000 site (Forests of the Flemish Ardennes and other South Flemish forests).
