Geography

Geography was a book written by, obtained by Ezio Auditore da Firenze in the 16th century in Constantinople.

Summary
''As the first systematic treatment of the principles of map-making, Ptolmey's "Geography" was one of the most influential books in the West. For more than a millenium after its completion in the second century CE, cartographers throughout Europe and Western Asia consulted Ptolmey's book for guidance, data and inspiration.

Source

 * Assassin's Creed: Revelations