The Via Postumia was an ancient Roman road of northern Italy constructed in 148 BC by the consul Spurius Postumius Albinus Magnus. It ran from the coast at Genua through the mountains to Dertona, Placentia (the termination of the Via Aemilia) and Cremona, just east of the point where it crossed the Po River. From Cremona the road ran eastward to Bedriacum, the current town of Calvatone, where it forked, one branch running to the right to Mantua, the other to the left to Verona, crossing the Adige river on the Ponte Pietra, the only bridge on the Adige river at that time, and then traversing the Venetian plain, crossing the Piave River at Maserada sul Piave until finally reaching Aquileia, an important military frontier town founded by Rome in 181 BC. The Roman conquest of Liguria depended