In particular the remarkable frontier lines which bounded the Roman provinces of Upper (southern) Germany and Raetia, and which at their greatest development stretched from near Bonn on the Rhine to near Regensburg on the Danube, are often called the Limes Germanicus.
As to the roads leading out of Italy, from Aquileia roads diverged northward into Raetia, eastward to Noricum and Pannonia, and southwards to the Istrian and Dalmatian coasts.
Not far from these ancient monuments is the new Raetian Museum, which contains a great collection of objects relating to Raetia (including the geological collections of the Benedictine monk of Disentis, Placidus a Spescha (1752-1833), who explored the high snowy regions around the sources of the Rhine).
It was an important point in the road system of the district, lying on that between Mediolanum and Aquileia, while here diverged to the north the roads up the Athesis valley and over the Brenner into Raetia, and to the south roads ran to Betriacum, Mantua and Hostilia.
A vague tradition connects the house with the Colonna family of Rome, or the Colalto family of Lombardy; but one more definite unites the Hohenzollerns with the Burkhardingers, who were counts in Raetia during the early part of the 10th century, and two of whom became dukes of Swabia.