Yuhanna ibn Sarabiyun (beginning of 9th century) known in Latin as Ibn Serapion, Yuhanna ibn Sarabiyun was a geographer. He authored a book on geography containing a description of the various seas, islands, lakes, mountains and rivers of the world. His descriptions of the Euphrates and Tigris and of the Nile are very significant. His account of the canals of Baghdad is our main basis of the reconstruction of the medieval plan of that city.
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