The Ill is a 72 km long tributary of the Rhine 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 the western Austria

Austria

Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...

n province of Vorarlberg

Vorarlberg

Vorarlberg is the westernmost federal-state of Austria. Although it is the second smallest in terms of area and population , it borders three countries: Germany , Switzerland and Liechtenstein...

.

It flows from the northern slopes of the Silvretta

Silvretta

The Silvretta Alps are a mountain range of the Central Eastern Alps shared by Tirol, Vorarlberg and Graubünden . The Austrian states of Tirol and Vorarlberg are connected by a pass road . The majority of the peaks are elevated above three thousand metres and are surrounded by glaciers...

 mountain range and then runs north-west through Vorarlberg. The Ill passes through the Montafon

Montafon

Montafon is a valley in Austria that extends from the city of Bludenz to the Silvretta mountain range. It is also known in the local dialect as Muntafu....

 and Walgau valleys and the town Feldkirch

Feldkirch, Vorarlberg

- Schools :* Bundesgymnasium und Bundesrealgymnasium Feldkirch * Bundeshandelsakademie und Bundeshandelsschule Feldkirch* Bundesoberstufenrealgymnasium und Bundesrealgymnasium Schillerstrasse...

. It joins the river Rhine a few kilometers northwest of Feldkirch ("Illspitz"), at the border with Switzerland

Switzerland

Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....

. The Ill has several dams with hydroelectric power stations.