Southern abutment of a Roman-era bridge in the central Isarco Gorge. The gorge is the principal barrier to every road (including the modern autostrada) from Verona to the easily crossed Brenner Pass. Northbound river-level traffic must switch from the left to the right bank at Blumau / Prato Isarco because a key Dolomite mountain, the Schlern, plunges sheer to the water further north.
The eight remaining layers of dressed stone have been dated and published by Vittorio Galliazzo. Neither the spans, the central pier nor the northern abutment of the bridge, which crossed high-volume, alpine-fed rapids, remain. There has been debate as to whether this difficult engineering challenge may have been the Pons Drusi marked on the Tabula Peutingeriana and nowhere else documented, but most authors reject this proposal.
See article, https://macrotypography.blogspot.de/2013/07/bridge-at-blumau.html" target="_blank">Bridge at Blumau, by Jean-Baptiste Piggin.