The 40.9 km long Mandau is a river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

 in Bohemia

Bohemia

Bohemia is a historical region in central Europe, occupying the western two-thirds of the traditional Czech Lands. It is located in the contemporary Czech Republic with its capital in Prague...

 (Czech Republic

Czech Republic

The Czech Republic is a landlocked country in Central Europe. The country is bordered by Poland to the northeast, Slovakia to the east, Austria to the south, and Germany to the west and northwest....

) and Saxony

Saxony

The Free State of Saxony is a landlocked state of Germany, contingent with Brandenburg, Saxony Anhalt, Thuringia, Bavaria, the Czech Republic and Poland. It is the tenth-largest German state in area, with of Germany's sixteen states....

 (Germany

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

).

It originates from multiple spring

Spring (hydrosphere)

A spring—also known as a rising or resurgence—is a component of the hydrosphere. Specifically, it is any natural situation where water flows to the surface of the earth from underground...

s north of the 580.6m (1902 feet AMSL) wulfs mountain (Czech: Vlčí hora, German: Wolfsberg) in the Šluknov Hook

Šluknov Hook

The Šluknov Hook or Šluknov Projection is a "panhandle" region found in the northern Czech Republic along the border with Germany. The area is part of the southern Lusatian Highlands, between the Elbe Sandstone Mountains in the west and the Lusatian Mountains in the east. It is administratively...

 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). From there the Mandau flows in southeast direction through Rumburk

Rumburk

Rumburk is a town in the Ústí nad Labem Region in the north of the Czech Republic. It has about 11,000 inhabitants and is famous because of its reportedly beautiful historical inner cities with many historical sights such as the old monastery...

 (Rumburg; Bohemia), Seifhennersdorf

Seifhennersdorf

Seifhennersdorf is a town in the district Görlitz, in the Free State of Saxony, Germany. It is situated on the border with the Czech Republic, and the Czech towns of Rumburk and Varnsdorf lie across the border to the north-east and south of town....

 (Saxony, Upper Lusatia

Upper Lusatia

Upper Lusatia is a region a biggest part of which belongs to Saxony, a small eastern part belongs to Poland, the northern part to Brandenburg. In Saxony, Upper Lusatia comprises roughly the districts of Bautzen and Görlitz , in Brandenburg the southern part of district Oberspreewald-Lausitz...

) and Varnsdorf

Varnsdorf

Varnsdorf is a town in the Ústí nad Labem Region of the Czech Republic, with a population of around 16,000. The town is close to the border with Germany, with border crossings to the Saxon towns of Seifhennersdorf and Großschönau, and is the second largest in the Děčín District.The village of...

 (Warnsdorf; Bohemia). Afterwards it flows eastwards through another part of the Upper Lusatia in which the Lausur

Lausur

Lausur is a river of Saxony, Germany.-See also:*List of rivers of Saxony...

 joins in Großschönau

Großschönau, Saxony

Großschönau is a municipality in the district Görlitz, in Saxony, Germany located in the Cross-border region with the Czech Republic. It used to be a famous Upper Lusatian center of Damask fabric production until the end of the 1980s...

, from Hainewalde

Hainewalde

Hainewalde is a village in Germany on the river Mandau, in the Bundesland of Saxony and the district Görlitz, historically belonging to the region Lusatia...

 through the Roschertal to Mittelherwigsdorf

Mittelherwigsdorf

Mittelherwigsdorf is a municipality in the district Görlitz, in Saxony, Germany....

, where the Landwasser

Landwasser (Mandau)

Landwasser is a river of Saxony, Germany....

 joins and finally reaches Zittau

Zittau

Zittau is a city in the south east of the Free State of Saxony, Germany, close to the border tripoint of Germany, Poland, and the Czech Republic. , there are 28,638 people in the city. It is part of the Görlitz district....

 where it flows east of the town 747 feet above sea level into the Lusatian Neisse

Lusatian Neisse

The Lusatian Neisse is a long river in Central Europe. The river has its source in the Jizera Mountains near Nová Ves nad Nisou, Czech Republic, reaching the tripoint with Poland and Germany at Zittau after , and later forms the Polish-German border on a length of...

.