The Bundesstraße 6 (abbr. B6) is a German federal highway running from Bremerhaven on the North Sea coast in a southeasterly direction through the states of Lower Saxony, Bremen, Saxony-Anhalt and Saxony to Görlitz on the Polish border.
East of Leipzig, the B6 (except of the ring roads around Meißen, Dresden and Bischofswerda) largely follows the historic course of the Via Regia Lusatiae Superioris, part of the medieval Via Regia.
In 1937, the northwestern section of the former Reichsstraße 6 (R6) was extended from Bremerhaven (Wesermünde) to Cuxhaven. Before World War II and the implementation of the Oder–Neisse line, the R6 road continued southeastwards from Görlitz via Hirschberg (present-day Jelenia Góra, Poland) and Schweidnitz (Świdnica) to the Silesian capital Breslau (Wrocław) and from there via Oels (Oleśnica) as far as the former Polish border near Groß Wartenberg (Syców). The sections between Görlitz/Zgorzelec and Syców then became part of the Polish National road 4 (today largely replaced by the A4 autostrada) and the National road 8.