Rubicon

The Rubicon (Latin: Rubicū, Italian: Rubicone) is a shallow river in northeastern Italy, about 80 kilometres long, running from the Apennine Mountains to the Adriatic Sea through the southern Emilia-Romagna region, between the towns of Rimini and Cesena. The Latin word rubico comes from the adjective "rubeus", meaning "red". The river was so named because its waters are colored red by mud deposits. It was key to protecting Rome from Civil War.

The idiom "Crossing the Rubicon" means to pass a point of no return, and refers to Julius Caesar's army's crossing of the river in 49 BC, which was considered an act of insurrection. Because the course of the river has changed much since then, it is impossible to confirm exactly where the Rubicon flowed when Caesar and his legions crossed it. The river is perhaps most known as the place where Julius Caesar uttered the famous phrase "alea iacta est" - the die is cast.