Ahmed Muhiddin Piri (1465/70–1553), better known as Piri Reis (Turkish: Pîrî Reis or Hacı Ahmed Muhiddin Pîrî Bey), was an Ottoman admiral, geographer, and cartographer.He is primarily known today for his maps and charts collected in his Kitab-ı Bahriye (Book of Navigation), a book that contains detailed information on navigation, as well as very accurate charts (for their time) describing the important ports and cities of the Mediterranean Sea.