The Polo Symbols: Arsenal

The Polo Symbols: Arsenal was a virtual representation of one of Ezio Auditore da Firenze's genetic memories, relived by Desmond Miles in 2012 through the Animus.

Description
Climbing to the top of tallest mast of the ship in the western part of the Harbor of Theodosius, Ezio scanned a Polo symbol on the dock just north of his position.

Outcome
Ezio located and unearthed the book titled The Book of Kings.

Reference

 * Assassin's Creed: Revelations