Caesar Crossing the Rubicon
An image of Julius Caesar and his army crossing the Rubicon River, which is located in northeastern Italy. The idiom "Crossing the Rubicon" refers to Julius Caesar passing this river in 49 BC, and means to pass a point of no return.
Ridpath, John Clark Cyclopedia of Universal History (Cincinnati, OH: The Jones Brothers Publishing CO., 1885)
Courtesy the private collection of Roy Winkelman