The German autobahns are the nationally coordinated motorway system in Germany. In German, they are officially called Bundesautobahn, which translates to federal expressways. German autobahns have no general speed limit, but advisory speed limit is 130 kmph (81 mph).
The total length of the network is 12819 km, or 7965 miles (in 2011), which ranks as the fifth longest in the world behind the Interstate Highway System of the United States, the National Trunk Highway System (NTHS) of the People’s Republic of China, the Highway System of Canada and the Autopistas of Spain.
Autobahns have multiple lanes of traffic in each direction, separated by a central barrier with grade-separated junctions and access restricted to motor vehicles with top speed of more than 60 kmph (37 mph).
The numbering system of German autobahns was introduced in 1974, in which autobahns are named by using capital letter A, which simply stands for “Autobahn” followed by a blank and a number (for example A 6). The main autobahns going across all across Germany have a single digit number. Shorter autobahns that are of regional importance (e.g. connecting two major cities or regions of Germany) have double digit number (e.g. A 24 connecting Berlin and Hamburg). Some very short autobahns which are just of local importance usually have three numbers (e.g. A 555).
The north-south autobahns are generally numbered using odd numbers from west to east; that is to say, the more easterly roads are given higher numbers. Similarly, the east-west routes are numbered using even numbers from north (lower numbers) to south (higher numbers).
Adolf Hitler enthusiastically embraced an ambitious autobahn construction project and appointed Fritz Todt the Inspector General of German Road Construction. Soon, over 100,000 labourers worked at construction sites all over Germany. As well as providing employment and improved infrastructure, necessary for economic recovery efforts, the project was also a great success for propaganda purposes.
The autobahns formed the first limited-access, high-speed road network in the world, with the first section from Frankfurt am Main to Darmstadt opening in 1935. This straight section was used for high speed record attempts by the Grand Prix racing teams of Mercedes-Benz and Auto Union until a fatal accident involving popular German race driver Bernd Rosemeyer in early 1938. The world record of 432 km/h (268 mph) set by Rudolf Caracciola on this stretch just prior to the accident remains one of the fastest speeds ever achieved on a public motorway.
Many sections of Germany’s autobahns are modern, containing three lanes in addition to an emergency lane. Some other sections remain in their original state, with two lanes, no emergency lane, and short slip-roads and ramps. Such a combination of the two types of autobahn can be seen on the A 9 autobahn (Munich–Berlin). Heading out from Munich, the autobahn starts off as modern, with five lanes in each direction as well as an emergency lane.