The Franks were probably the first to build a road network that allowed safe travel from Valtellina to the regions beyond the Alps via the Bormio area, but the dukes of Milan deserve mention for the privileges they granted to merchants from Bormio in the practice of their trade.
The two main roads connecting Bormio with Tyrol—known as “royal roads” because they fell under sovereign authority—were the Fraele and the Umbrail routes. The former was safer with a single steep incline, while the latter offered faster travel times; in the Middle Ages, they were known respectively as the “Via Longa” and the “Via Curta de Venosta.”
The most commonly traded goods were wine and salt. The former, purchased in Valtellina, was resold in regions beyond the Alps at a substantial profit; the latter was purchased in Tyrol, at the salt mines near the town of Hall, close to Innsbruck, and sold in Lombardy.
The caravans crossing the pass toward the German region could consist of several dozen pack animals. The animals were loaded with two barrels on either side of the pack saddle and a third, smaller one on their backs; the average amount of wine carried by a horse was about 126 liters, equivalent to a “soma,” the unit of measurement for all kinds of goods carried by pack animals.
During the winter months, the mountain pass was crossed using horse-drawn sleds; in fact, the road had to be passable in every season, as evidenced by the contracts with the “rotteri”—brave men dressed in heavy woollen garments who, risking their lives, “broke up” the snowpack to avert the danger of avalanches.