I never knew where the Rubicon was. The history books make it sound as though it were way
north, not far from the Alps, when they say it was boundary of Cisalpine Gaul. So I hunted
until I found it. It's not on any may I could find. I did learn that it was a small river flowing into
the Adriatic, close to present day Rimini. That's about the width of the Italian peninsula north
of Rome, but on the Adriatic. The best route to Gaul from Rome in those times required quite a
detour. The history books don't say much about why Caesar was willing to spend eight years in Gaul.
He was ppor when he went, and got so rich from his share of slaves captured and sent to Rome, he
became one of the richest men in Rome. After Crassus stupidly got himself bumped off, only Pompey
was richer than Caesar. Surprisingly Pompey left Italy, Caesar went after him and after losing one big
battle, destroyed Pompey's army. Pompey fled to Egypt, and was murdered there.

So now we know where the Rubicon was. Approximately.

From the World Book 2002 article on the Rubicon:

The name Rubicon comes from the Latin word rubeus meaning red. The stream got its name because its waters are colored red by mud deposits. It may be the same as the present-day Fiumicino River.

the present-day Fiumicino River.

Or either that or it moved to America and became the Colorado, one.

Which is the relationship between Fiumicino and the colours?
Fiumicino means just "piccolo fiume" = small river