The Saulx is a 115 km long 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 France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

, right tributary of the Marne

Marne River

The Marne is a river in France, a right tributary of the Seine in the area east and southeast of Paris. It is long. The river gave its name to the départements of Haute-Marne, Marne, Seine-et-Marne, and Val-de-Marne....

. Its source is near the village Germisay

Germisay

Germisay is a commune in the Haute-Marne department in north-eastern France....

. It flows generally northwest, through the following départements

Départements of France

The departments of France are French administrative divisions. The 101 departments form one of the three levels of local government, together with the 22 metropolitan and 5 overseas regions above them and more than 36 000 communes beneath them...

and towns:

• Haute-Marne
  Haute-Marne
  Haute-Marne is a department in the northeast of France named after the Marne River.-History:Haute-Marne is one of the original 83 departments created during the French Revolution on March 4, 1790...
  
  : Effincourt
  Effincourt
  Effincourt is a commune in the Haute-Marne department in north-eastern France....
  
  
• Meuse
  Meuse
  Meuse is a department in northeast France, named after the River Meuse.-History:Meuse is one of the original 83 departments created during the French Revolution on March 4, 1790...
  
  : Montiers-sur-Saulx
  Montiers-sur-Saulx
  Montiers-sur-Saulx is a commune in the Meuse department in Lorraine in north-eastern France.-See also:*Communes of the Meuse department...
  
  , Stainville
  Stainville
  Stainville is a commune in the Meuse department in Lorraine in north-eastern France....
  
  
• Marne
  Marne
  Marne is a department in north-eastern France named after the river Marne which flows through the department. The prefecture of Marne is Châlons-en-Champagne...
  
  : Sermaize-les-Bains
  Sermaize-les-Bains
  Sermaize-les-Bains is a commune in the Marne department in north-eastern France.-See also:*Communes of the Marne department...
  
  , Pargny-sur-Saulx
  Pargny-sur-Saulx
  Pargny-sur-Saulx is a commune in the Marne department in north-eastern France.Pargny-sur-Saulx is known for its tiles, which are exported sometimes to Singapore, giving it the nickname "the city of the tiles"...
  
  , Vitry-le-François
  Vitry-le-François
  Vitry-le-François is a commune in the Marne department in north-eastern France. It is located on the Marne River and is the western terminus of the Marne-Rhine Canal.- History :In 1142, Louis VII invaded Champagne and seized Vitry-le-François...
  
  

The Saulx flows into the Marne in Vitry-le-François

Vitry-le-François

Vitry-le-François is a commune in the Marne department in north-eastern France. It is located on the Marne River and is the western terminus of the Marne-Rhine Canal.- History :In 1142, Louis VII invaded Champagne and seized Vitry-le-François...

. Its main tributaries are the Ornain

Ornain

The Ornain is a 116 km long river in northeastern France, right tributary of the Saulx . It is formed near the village Gondrecourt-le-Château by the confluence of the small rivers Ognon and Maldite. It flows generally northwest...

 and the Chée

Chée

The Chée is a long river in the Meuse and Marne départements, northeastern France. Its source is in the Barrois, near Marat-la-Grande, a hamlet in Les Hauts-de-Chée. It flows generally southwest...

. The part of the Marne-Rhine Canal

Marne-Rhine Canal

The Marne-Rhine Canal is a canal in north eastern France. It connects the river Marne in Vitry-le-François with the Rhine in Strasbourg. Combined with the canalised part of the Marne, it allows transport between Paris and eastern France. The original objective of the canal was to connect Paris...

between Vitry-le-François and Sermaize-les-Bains runs parallel to the Saulx.