(The Book of Lands) is a masterpiece of medieval Islamic geography. Written in the 9th century by the famous historian and geographer Ahmad al-Ya'qubi (and later by another scholar named Ibn al-Faqih under the same title), this text remains a foundational source for understanding the geography, administration, and cultures of the Abbasid Caliphate and its neighbors.
Al-Ya‘qubi does not merely tell you that a city exists; he tells you how it is governed. The text is famous for detailing the kharaj (land tax) of various provinces. This makes the book invaluable not just for geographers, but for economic historians trying to understand the fiscal machinery of the Abbasid empire. kitab al-buldan english pdf