Tiber

Ezio leaping over the River Tiber.

The Tiber was a river that ran through the city of Rome, Italy, which separated the Vaticano district from the rest of the city. The Castel Sant'Angelo rested on the river bank, whilst Tiber Island, the only island upon the river, could be found further south.

Bridges

There are six bridges built over the river, allowing civilians to cross the river from various points in the city. Among these are the Ponte Sant'Angelo and the Ponte Sisto.

Only two of these bridges cross the river to Tiber Island; both of which are marked with the Templar Cross. Interestingly, no other bridge in Rome has these symbols, yet Tiber Island houses the Assassins' headquarters.

Trivia

• Ezio Auditore considers dropping the Apple into the Tiber at the beginning of Assassin's Creed: Brotherhood.
• There are hidden entrances into the Tiber Island headquarters submerged in the Tiber.
• The iconic scene of the Assassin Ceremony ends with the newly-initiated Assassin performing a Leap of Faith into the river.

Source

• Assassin's Creed: Brotherhood