The main river tributaries extend through the Black and Caspian Seas, occupying territories that are now known as Georgia, Azerbaijan and most of eastern Turkey, including Mount Ararat.
The map belongs to the third period of the old Portuguese navigational cartography which is characterized by decrease of the influence of the Ptolemy notions of orientation and greater accuracy of depictions of countries and continents.
Douradu’s well-known works are noted for the high quality and beauty of performance. He was one of the most outstanding cartographers of his time. Most of his hand-written maps are of relatively large scale and have been included in navigational atlases.