Piri Re'is, Map of the Americas (1513)

Pris Re'is, a Turkish naval captain, created this  map (of which only the western third remains) in 1513, depicting the world as it was known to the Ottoman Empire in the 16th century. An annotation on the map explains that 20 maps were used to create this one, including those of Alexander the Great, Ptolemy, Columbus, and "four maps recently made by the Portuguese." The map shows the Spanish and Portuguese discoveries of the 15th and 16th centuries, including the landfalls made along the coasts of the Americas, and is the only 16th-century map to correctly locate South America in its correct longitudinal position relative to Africa. However, the coast of North America and the southern coast of South America are distorted, with South America portrayed as having an unusual curved shape.  Some historians speculate that the awkward shape of South America was an attempt to give Portugal more land than what the 1494 Treaty of Tordesillas dictated.  The copious notes and numerous place names on the map provide insight into the geographical knowledge circulated between the Ottoman Empire and Christian Europe. However, questions remain as to how Piri Re'is obtained information on Spain and Portugal's latest discoveries, since they would have been treated as closely guarded secrets at the time.