The Ilm is a 128.7 kilometres (80 mi) 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 Thuringia

Thuringia

The Free State of Thuringia is a state of Germany, located in the central part of the country.It has an area of and 2.29 million inhabitants, making it the sixth smallest by area and the fifth smallest by population 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 is a left tributary of the Saale

Saale

The Saale, also known as the Saxon Saale and Thuringian Saale , is a river in Germany and a left-bank tributary of the Elbe. It is not to be confused with the smaller Franconian Saale, a right-bank tributary of the Main, or the Saale in Lower Saxony, a tributary of the Leine.-Course:The Saale...

, into which it flows in Großheringen

Großheringen

Großheringen is a municipality in the Weimarer Land district of Thuringia, Germany....

 near Bad Kösen

Bad Kösen

' is a spa town in Germany, on the Saale river in the small German wine-growing region of Saale-Unstrut. It is a former municipality in the Burgenlandkreis district, in Saxony-Anhalt...

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Towns along the Ilm are Ilmenau

Ilmenau

Ilmenau is a town located in the district of Ilm-Kreis, Thuringia, Germany.Ilmenau is situated in the valley of the Ilm river, at an altitude of 431 metres above sea level, and is the biggest town in Ilm-Kreis district, with 6,200 students studying at the Technische Universität Ilmenau. The...

, Stadtilm

Stadtilm

Stadtilm is a town in the Ilm-Kreis district, in Thuringia, Germany. It is situated on the river Ilm, 15 km northeast of Ilmenau, and 11 km southeast of Arnstadt....

, Kranichfeld

Kranichfeld

Kranichfeld is a town in the Weimarer Land district, in Thuringia, Germany. It is situated on the river Ilm, 18 km southeast of Erfurt, and 16 km southwest of Weimar....

, Bad Berka

Bad Berka

Bad Berka is a German city, situated in the south of Weimar region in the state of Thuringia. With its almost 8.000 inhabitants Bad Berka is the second biggest city in Weimarer Land district . The river flowing through the city, which is embedded in new red sandstone, is called Ilm.Bad Berka is a...

, Weimar

Weimar

Weimar is a city in Germany famous for its cultural heritage. It is located in the federal state of Thuringia , north of the Thüringer Wald, east of Erfurt, and southwest of Halle and Leipzig. Its current population is approximately 65,000. The oldest record of the city dates from the year 899...

, Apolda

Apolda

Apolda is a town in central Thuringia, Germany, the capital of the Weimarer Land district. It is situated in the center of the triangle Weimar - Jena - Naumburg near the river Ilm, c. 15 km east by north from Weimar, on the main line of railway from Berlin via Halle, to...

 and Bad Sulza

Bad Sulza

*anthonys wiilyBad Sulza is a town in the Weimarer Land district, in Thuringia, Germany. It is situated on the river Ilm, 15 km southwest of Naumburg, and 18 km north of Jena....

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In the valley of Ilm river runs the federal motorway

Bundesstraße

Bundesstraße , abbreviated B, is the denotation for German and Austrian national highways.-Germany:...

 87 from Ilmenau to Leipzig

Leipzig

Leipzig Leipzig has always been a trade city, situated during the time of the Holy Roman Empire at the intersection of the Via Regia and Via Imperii, two important trade routes. At one time, Leipzig was one of the major European centres of learning and culture in fields such as music and publishing...

 and two railways: the Thuringian Railway between Großheringen and Weimar and the Ilm Railway (Ilmbahn) between Kranichfeld and Weimar. Part of the Nuremberg–Erfurt high-speed railway is also being built in the upper part of the valley near Ilmenau.