 This road, named an imperial highway ("Reichstrasse") in 1433, was one of the most important thoroughfares in Germany up until the late Middle Ages.In medieval documents, the road is often referred to as the "Kaiserstraße", the emperor's highway, because over the centuries many high ranking personalities used the imperial highway.The Roman general Julian (359), the king of the Huns Attila (451), king Conrad III (1150), king Philipp of Swabia (1199), emperor Frederick II (1205), and king Henry VII (1224) all sojourned past the place where Horrenberg stands today.