The Salzach is a tributary of the Danube, and the brown Danube runs, with its tentacles of tributaries, from west of Bavaria through central Europe to the Black Sea. The salt could be boiled in cylindrical molds, much as it still is in Saharan Africa, and the cylinders could be loaded in barges that traveled the Salzach to Passau, where it entered the Danube, to be traded in Germany or central Europe.
