The Trevi Fountain is probably the largest Baroque fountain in Rome. By the 31st century, the only thing that's changed in a 1000 years is its guardian, who is now a giant alien octopus.
The Professor went there because of the three points on Neptune's trident, and the V, which is the way the U in his name is written.
The fountain's sewer hole is a secret passage to the Roman Pantheon that was used by the Professor, Fry, Leela, and Bender to stay on track of the greatest mystery of all time.
- When the crew visited it, Bender got 48 cents, and a giant nickel that turned out to be the key necessary to uncover Leonardo da Vinci's lost workshop.