File:1556 map of Sumatra by Giacomo Gastaldi.jpg

English: This fine woodcut map of Sumatra is the first separate map of an Indonesian island to be based on actual empirical data. It is based on Delle Navigationi et Viaggi (Navigations and travels) by Giovanni Battista Ramusio, which was published in three volumes in Venice in 1550-59. Ramusio was a Venetian diplomat, geographer, and historian.

Delle Navigationi et Viaggi is a massive work that includes Ramusio's translations into Italian of many first-hand accounts of the exploration, up to the mid-16th century, of Africa, the New World, and Asia, along with maps by the Venetian cartographer Giacomo Gastaldi (circa 1500-circa 1565). The book contains an account of the voyage of the Parmentier brothers, Frenchmen who landed on the west coast of Sumatra in 1529 in defiance of the Portuguese monopoly on the spice trade in the East Indies and their blockade on foreign access to the island. Both brothers subsequently died of fever. Prior to the publication of Ramusio's map, Sumatra had been confused with Sri Lanka and maps of the island were largely conjectural, based primarily on the writings of Marco Polo.

The map is oriented with south at the top. The shape of the island and many of its features are quite accurately portrayed. No part of the nearby Malay Peninsula or the island of Java is shown, although several of the surrounding small islands, such as Bancha (present-day Bangka), are displayed. The interior of the map is illustrated with scenes that depict vegetation, animals, and native figures at work and play; the surrounding seas contain ships and numerous creatures, both real and imaginary.