The Friedberger Ach is a small 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 Bavaria

Bavaria

Bavaria, formally the Free State of Bavaria is a state of Germany, located in the southeast of Germany. With an area of , it is the largest state by area, forming almost 20% of the total land area of Germany...

, 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 is a right tributary of the Danube

Danube

The Danube is a river in the Central Europe and the Europe's second longest river after the Volga. It is classified as an international waterway....

. Its source is in the village Untermühlhausen, northeast of Landsberg am Lech

Landsberg am Lech

Landsberg am Lech is a town in southwest Bavaria, Germany, about 65 kilometers west of Munich and 35 kilometers south of Augsburg. It is the capital of the district of Landsberg am Lech....

. For most of its length it flows parallel to the river Lech

Lech River

The Lech is a river in Austria and Germany. It is a right tributary of the Danube in length with a drainage basin of .Its source is located in the Austrian state of Vorarlberg, where the river rises from lake Formarinsee in the Alps at an altitude of...

 at only a few km distance. Towns along the Friedberger Ach include Weil

Weil, Bavaria

Weil is a municipality in the district of Landsberg in Bavaria in Germany.-World heritage site:It is home to one or more prehistoric pile-dwelling settlements that are part of the Prehistoric Pile dwellings around the Alps UNESCO World Heritage Site....

, Prittriching

Prittriching

Prittriching is a municipality in the district of Landsberg in Bavaria in Germany....

, Mering

Mering

Mering is a municipality in the district Aichach-Friedberg, in Bavaria, Germany. It is located on the river Paar.First mentioned in record in 1021, Mering has a long history....

, Friedberg

Friedberg, Bavaria

Friedberg is a city in the district Aichach-Friedberg, Bavaria, Germany, with some 30,000 inhabitants. It is located next to Augsburg at the Lech river...

, Rehling

Rehling

Rehling is a municipality in the district of Aichach-Friedberg in Bavaria in Germany....

, Thierhaupten

Thierhaupten

Thierhaupten is a market town in south-central Germany in the district of Augsburg in the Swabia administrative region of Bavaria, and is located at the Lech river valley.-Districts:There are 8 town districts in Thierhaupten:...

 and Rain

Rain (Lech)

Rain is a municipality in the Donau-Ries district, in Bavaria, Germany. It is situated on the river Lech, close to its confluence with the Danube, 11 km east of Donauwörth....

. After Rain, the Friedberger Ach flows east, parallel to the Danube, and joins the Danube near Oberhausen

Oberhausen (near Neuburg)

Oberhausen is a municipality in the Neuburg-Schrobenhausen district in the state of Bavaria in Germany.Oberhausen combines historic Oberhausen, Unterhausen, Sinning and Kreut....

.