It lay on the territory of the present German states of Rhineland-Palatinate, Hesse, Baden-Württemberg and Bavaria. To the north, it bordered those parts of the Roman province of "Rhaetia" that lay north of the Danube and guarded the eastern border of that part of "Germania Superior" that lay east of the Rhine. In Upper Germania the border defences initially consisted only of a post road. From about 162/63 AD, the Romans constructed a defensive barrier with watchtowers and signal towers, palisades, ditches and earthworks. On one short section of the Rhaetian Limes, a solid stone wall was erected. In its final stages, the Upper Germanic-Rhaetian Limes was about 550 kilometres long and ran from Rheinbrohl, in the county of Neuwied in northern Rhineland-Palatinate, as far as Hienheim on the Danube. Between the villages of Osterburken and Welzheim, the "limes" ran for 81 kilometres almost in a straight line southwards. In the scholarly literature, this unusual section is considered as evidence that this type of boundary wall had never been used for defensive purposes.