As his name indicates, he originated in the Maghrib, but his major astronomical activities took place in Cairo during the second half of the 13th century. Marrākushī is best known for work devoted to spherical astronomy and astronomical instrumentation, entitled Jāmi` al-mabādi’ wa-’l-ghāyāt fī `ilm al-mīqāt (Collection of the principles and objectives in the science of timekeeping), which is intended as a comprehensive encyclopedia of practical astronomy; it was the standard reference work for Mamluk Egyptian and Syrian, Rasūlid Yemeni, and Ottoman Turkish specialists of the subject. The arrival of Marrākushī in Cairo coincided with the establishment of the first offices of muwaqqits (timekeepers) in Egyptian mosques. Marrākushī must have died, most probably in Cairo, between 1281/1282 and ca 1320, since 2 early 14th-c. sources refer to him as being deceased (an anonymous treatise on timekeeping entitled Kanz al-yawāqīt, datable to 723 H/1323 and preserved in MS Leiden Or. 468, f. 91r, and a treatise on instrumentation by Najm al-Dīn al-Miṣrī composed in Cairo ca 1330). [F. Charette, see BEA]