A ring road (also known as beltline, beltway, circumferential (high)way, loop or orbital) is a road or a series of connected roads encircling a town or city.

Bundesautobahn 10 (translates from German as Federal Motorway 10, short form Autobahn 10, abbreviated as BAB 10 or A 10) runs in Brandenburg as an orbital motorway around the German capital Berlin, colloquially called Berliner Ring. It should not be confused with the Berliner Stadtring (Bundesautobahn 100) around Berlin's inner city.

With a total length of 196 km (122 mi), the BAB 10 is the longest orbital in Europe, being 8 km (5.0 mi) longer than the London M25 motorway.

The first sections near Werder, Schwanebeck and Spreeau were built from 1936 until the outbreak of World War II in 1939 as part of the Reichsautobahn program. Construction works were not resumed until 1972, when the East German authorities had the orbital completed until 1979, then also to bypass West Berlin on the way from the capital East Berlin to Potsdam and the motorways leading to Magdeburg and Leipzig.

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