is a

motorway A controlled-access highway is a type of highway that has been designed for high-speed vehicular traffic, with all traffic flow—ingress and egress—regulated. Common English terms are freeway, motorway and expressway. Other similar terms i ...

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

. It branches off the A 3 at the

Würzburg Würzburg (; Main-Franconian: ) is a city in the region of Franconia in the north of the German state of Bavaria. Würzburg is the administrative seat of the ''Regierungsbezirk'' Lower Franconia. It spans the banks of the Main River. Würzburg is ...

-West triangle and ends near the border with

Switzerland ). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Luzern, Neuchâtel ...

. The oldest part of the A 81 between the

Weinsberg Weinsberg (South Franconian: ''Weischberg'') is a town in the north of the state of Baden-Württemberg in Germany. It was founded around 1200 and is situated in the Heilbronn district. The town has about 11,800 inhabitants. It is noted for its win ...

intersection ( A 6) near

Heilbronn Heilbronn () is a List of cities and towns in Germany, city in northern Baden-Württemberg, Germany, surrounded by Heilbronn (district), Heilbronn District. With over 126,000 residents, it is the sixth-largest city in the state. From the late Mid ...

and

Dreieck Leonberg is a motorway in Germany. It branches off the A 3 at the Würzburg-West triangle and ends near the border with Switzerland. The oldest part of the A 81 between the Weinsberg Weinsberg (South Franconian: ''Weischberg'') is a town in ...

( A 8) near

Stuttgart Stuttgart (; Swabian: ; ) is the capital and largest city of the German state of Baden-Württemberg. It is located on the Neckar river in a fertile valley known as the ''Stuttgarter Kessel'' (Stuttgart Cauldron) and lies an hour from the ...

was finished in the years 1938 to 1940. This section included the first tunnel built for an autobahn, the first Engelberg tunnel near

Leonberg Leonberg (; swg, Leaberg) is a town in the German federal state of Baden-Württemberg about to the west of Stuttgart, the state capital. About 45,000 people live in Leonberg, making it the third-largest borough in the rural district (''Landkr ...

. When Weinsberg-Leonberg was upgraded to 3+3 lanes in the 1970s, the tunnel with its two lanes each and steep grades (up to 6%) became something of a bottleneck. In 1999 a new Engelberg tunnel was opened. Original plans called for the A 81 to be continued northwards skirting the north-west of Würzburg to join up with the A 7, but these plans were later abandoned. Instead, the A 81 shares a part of the A 8 to the Stuttgart intersection and then continues south on a motorway that was built as A 831 to Gärtringen, where it meets the original line again at a partly finished intersection. As a result of this change of plans, Gärtringen became one of the few exits in the German autobahn network that leave to the left. Further south, the terrain required some spectacular engineering, including a bridge near Horb that spans 125 m above the

Neckar The Neckar () is a river in Germany, mainly flowing through the southwestern state of Baden-Württemberg, with a short section through Hesse. The Neckar is a major right tributary of the Rhine. Rising in the Schwarzwald-Baar-Kreis near Schwenn ...

river. Currently, the A 81 ends near

Singen Singen (Low Alemannic German, Low Alemannic: ''Singe'') is an industrial city in the very south of Baden-Württemberg in southern Germany and just north of the German-Swiss border. Location Singen is an industrial city situated in the very south ...

Exit list

(Hohentwiel)

External links

{{bundesautobahn 81 A081 A081