It was Caliph Al-Ma'mum who bagan the Muslim tradition of building observatories for studying the stars and planets when he founded facilities in Al-Shammasiyah quarter, in Baghdad, and on Mount Qasiyun, in Damascus. Other rulers later established large observatories like Malikshah, in Isfahan; Maragha, in East Azerbijan; Ulugh Beg, in Samarkand, Uzbekistan; and Taqi al-Din, in Istanbul depicted in this 16th-century Turkish manuscript from the 'Book of the Kings'.