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Muhammad al-Idrisi (Dreses)

Abu Abdullah Muhammad al-Idrisi al-Qurtubi al-Hasani as-Sabti, (Latin: Dreses) was an Arab Muslim geographer, cartographer and Egyptologist who lived in Palermo, Sicily at the court of King Roger II. Muhammed al-Idrisi was born in Ceuta, then belonging to the Almoravids.Early life

Al-Idrisi was born into the large Hammudid family of North Africa and Al-Andalus, which claimed descent from the Idrisids of Moroccoand ultimately the prophet Muhammad.

Al-Idrisi was born in the city of Ceuta, where his great-grandfather had been forced to settle after the fall of Hammudid Málaga to the Zirids of Granada. He spent much of his early life travelling through North Africa and Al-Andalus (Muslim Spain of the times) and seems to have acquired detailed information on both regions. He visited Anatolia when he was barely 16. He studied in Córdoba.

His travels took him to many parts of Europe including Portugal, the Pyrenees, the French Atlantic coast, Hungary, and Jórvík (now known as York).

The Tabula Rogeriana, drawn by al-Idrisi for Roger II of Sicily in 1154, one of the most advanced ancient world maps. Modern consolidation, created from al-Idrisi's 70 double-page spreads, shown upside-down as the original had South at the top. Because of conflict and instability in Al-Andalus al-Idrisi joined contemporaries such as Abu al-Salt in Sicily, where the Normans had overthrown Arabs formerly loyal to the Fatimids.

Al-Idrisi incorporated the knowledge of Africa, the Indian Ocean and the Far East gathered by Islamic merchants and explorers and recorded on Islamic maps with the information brought by the Norman voyagers to create the most accurate map of the world in pre-modern times, which served as a concrete illustration of his Kitab nuzhat al-mushtaq, (Latin: Opus Geographicum), which may be translated A Diversion for the Man Longing to Travel to Far-Off Places.

Tabula Rogeriana

The Tabula Rogeriana was drawn by Al-Idrisi in 1154 for the Norman King Roger II of Sicily, after a stay of eighteen years at his court, where he worked on the commentaries and illustrations of the map. The map, with legends written in Arabic, while showing the Eurasian continent in its entirety, only shows the northern part of the African continent and lacks details of the Horn of Africa and Southeast Asia.

For Roger it was inscribed on a massive disc of solid silver, two metres in diameter.

On the geographical work of al-Idrisi, S.P. Scott wrote in 1904:

The compilation of Edrisi marks an era in the history of science. Not only is its historical information most interesting and valuable, but its descriptions of many parts of the earth are still authoritative. For three centuries geographers copied his maps without alteration. The relative position of the lakes which form the Nile, as delineated in his work, does not differ greatly from that established by Baker and Stanley more than seven hundred years afterwards, and their number is the same. The mechanical genius of the author was not inferior to his erudition. The celestial and terrestrial planisphere of silver which he constructed for his royal patron was nearly six feet in diameter, and weighed four hundred and fifty pounds; upon the one side the zodiac and the constellations, upon the other-divided for convenience into segments-the bodies of land and water, with the respective situations of the various countries, were engraved.

Al-Idrisi inspired Islamic geographers such as Ibn Battuta, Ibn Khaldun and Piri Reis. His map also inspired Christopher Columbus and Vasco Da Gama. Description of islands in the North Sea

Al-Idrisi in his famous Tabula Rogeriana mentioned Irlandah-al-Kabirah (Great Ireland). According to him, "from the extremity of Iceland to that of Great Ireland," the sailing time was "one day." Although historians note that both al-Idrisi and the Norse tend to understate distances, the only location this reference is thought to have possibly pointed to, must likely have been in Greenland.

Nuzhat al-Mushtaq

As well as the maps, al-Idrisi produced a compendium of geographical information with the title Kitab nuzhat al-mushtaq fi'khtiraq al-'afaq. The title has been translated as The book of pleasant journeys into faraway lands or The pleasure of him who longs to cross the horizons. It has been preserved in nine manuscripts, seven of which contain maps.

The translated title of this work (in the "pleasure of him ..." form) attracted favourable comment from the team selecting lists of names for features expected to be discovered by the New Horizons probe reconnoitring the Pluto system. The Al-Idrisi Montes is a geographical feature in that system named after him.

In the introduction, al-Idrisi mentions two sources for geographical coordinates: Ptolemy and "an astronomer" that must be ibn al-Hasan al-Zayyat; and states that he has cross-checked oral reports from different informers to see if geographical coordinates were consistent.