Rubicon

The Rubicon is a river that flows into the Adriatic Sea south of Ravenna, Italy. In the time of Julius Caesar, a river with this name was the border between the Roman province Gallia Cisalpina, and Italy, which was not a province at the time. The exact river Caesar referred to is unknown; the river that is known as "Rubicone" today was selected and named by Benito Mussolini.