Bundesautobahn 559 (translates from German as Federal Motorway 559, short form Autobahn 559, abbreviated as BAB 559 or A 559) is an autobahn in Germany. The A 559 is a former alignment of the A 59. The A 59 was rerouted in the 1980s to relieve congestion at the Gremberg four-way interchange with the A 4. The primary function of the A 559, besides relieving traffic at the A 4 interchange, is to connect the Cologne-Bonn Airport to Cologne proper. The airport is along the A 59, one junction south of the A 559's southern terminus. The section of road from the junction Köln-Vingst (just after the A 4) to the end of the freeway at Köln-Deutz is up to autobahn standards, but is only designated as the L 124. This stretch of road was signed at one time as the A 559, although the autobahn designation never officially covered the entire freeway. From Wikipedia
