The 40.9 km long Mandau (Czech: Mandava) is a river in Bohemia (Czech Republic) and Saxony (Germany). It is a left tributary of the Lusatian Neisse, which it joins near Zittau.It originates from multiple springs north of the 580.6m (1902 feet AMSL) Wolf Mountain (Czech: Vlčí hora, German: Wolfsberg) in the Šluknov Hook, which join in Panský (German: Herrnwalde) at 1690 feet above sea level. Coming from Zahrady (German: Gärten) another stream joins in Nové Křečany (Neu Ehrenberg).