The Rubicon is a shallow river in northeastern Italy, just south of Ravenna. The same name was given to a river that was famously crossed by Julius Caesar in 49 BCE. While it has not been proven, historians generally agree that the two rivers are indeed one and the same.

The modern-day river flows for around 80 km (50 mi) from the Apennine Mountains to the Adriatic Sea through the south of the Emilia-Romagna region, between the towns of Rimini and Cesena. The Latin word Rubicō comes from the adjective rubeus, meaning "red". The river was so named because its waters are colored red by mud deposits.

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