Bundesautobahn 643 (translates from German as Federal Motorway 643, short form Autobahn 643, abbreviated as BAB 643 or A 643) is a 8.4-kilometer (5.2 mi) short autobahn in Germany. The motorway crosses the Rhine River, connecting the cities of Wiesbaden and Mainz, the capital cities of the German states of Hesse and Rhineland-Palatinate, respectively. It is one of two autobahns in Germany that connect two neighboring state capitals in only one exit. However short the A 643 may be, it is a vital link within the Frankfurt Rhine-Main Region, being only one of three routes across the Rhine in the region. It is an important connection between Autobahn 66 on the north bank of the Rhine and A 60 south of Mainz.
