B8) is a German federal highway in southwestern Germany of great historical importance.

It has existed since the 9th century, known then as Via Publica, and until recent times was a key trade route linking the towns of Brussels, Duisburg, Cologne, Frankfurt, Würzburg, Nuremberg, Regensburg and Passau.

In the Middle Ages it joined the commercial cities of Cologne, Frankfurt, Nuremberg and Regensburg.

In 1615, the general postmaster Lamoral von Taxis was tasked by emperor Matthias with setting up a postal route between Brussels and Prague, via Frankfurt and Nuremberg.

The medieval trade route largely used dry level roads rather than the valleys, which were swampy and impassible after rain.