Bundesstraße
One distinguishing characteristic between German "Bundesstraßen" and "Autobahnen" is that there usually is a general 100 km/h (62 mph) speed limit on federal highways out of built-up areas, as opposed to the merely advisory speed limit ("Richtgeschwindigkeit") of 130 km/h (83 mph) in unmarked sections of the autobahns. However, a number of "Bundesstraßen" have been extended as expressways (dual carriageways) (colloquially called "Yellow Autobahns"). Many of these have speed limits of usually 100–120 km/h, others have only an advisory speed limit like autobahns. Most sections of the federal highways are only single carriageway with one lane for each direction and no hard shoulder pull-out area.
Speed limits in Germany
Legally, however, state and even local authorities have the power to enact speed limits. The district of Köln / (Cologne) has posted a speed limit on the heavily frequented Kölner Autobahnring / (Cologne Beltway). Effective 9 April 2008, the City-State of Bremen began enforcing a general 120 km/h (75 mph) speed limit, citing environmental concerns. However, Bremen's new limit only impacted an additional 11 kilometers of Bremen's 60 kilometers of Autobahn; most Bremen motorways already had some speed restriction due to congestion and noise.