The German autobahns form the nationally coordinated motorway
system in Germany. In German, they are officially called
Bundesautobahn (plural Bundesautobahnen, abbreviated 'BAB'),
which translates to "federal expressways". German autobahns have
no general speed limit, but the advisory speed limit
(Richtgeschwindigkeit) is 130 kilometres per hour (81 mph).
Germany's autobahn network has a total length of about 12,845
kilometres (7,982 mi) in 2012, which ranks as the fifth longest
highway system in the world behind the National Trunk Highway
System (NTHS) of China (95,600 km), the Interstate Highway
System of the United States (75,932 km), the expressways of
Canada (17,000 km) and the highways in Spain (15,152 km). These
motorways are officially named Bundesautobahn (BAB), if their
building and maintenance is ordered by the federal government.
The German States are actually responsible for the roads on a
federal plan of the transport system acting as the constructors
in cases of network extensions. Some Bundess