During this period, the Great Mosque of Kairouan was both a place of prayer and a center for teaching Islamic sciences under the Maliki current. One may conceivably compare its role to that of the University of Paris during the Middle Ages. In addition to studies on the deepening of religious thought and Maliki jurisprudence, the mosque also hosted various courses in secular subjects such as mathematics, astronomy, medicine and botany. The transmission of knowledge was assured by prominent scholars and theologians which included Sahnun ibn Sa'id and Asad ibn al-Furat, eminent jurists who contributed greatly to the dissemination of the Maliki thought, Ishaq ibn Imran and Ibn al-Jazzar in medicine, Abu Sahl al-Kairouani and Abd al-Monim al-Kindi in mathematics. Thus the mosque, headquarters of a prestigious university with a large library containing many scientific and theological works, was the most remarkable intellectual and cultural center in North Africa during the ninth, tenth and eleventh centuries. A unique religious tradition in Kairouan was the use of Islamic law to enforce monogamy by stipulating it in the marriage contract, a practice common among both elites and commoners. This stipulation gave a woman legal recourse in the case that her husband sought to take a second wife. Although the introduction of the 1956 Code of Personal Status rendered the tradition obsolete by outlawing polygamy nationwide, some scholars have identified it as a "positive tradition for women within the large framework of Islamic law." The city's main attraction is the Great Mosque of Sidi-Uqba, which is said to largely consist of its original building materials. In fact most of the column stems and capitals were taken from ruins of earlier-period buildings, while others were produced locally. There are 414 marble, granite and porphyry columns in the mosque. Almost all were taken from the ruins of Carthage. Previously, it was forbidden to count them, on pain of blinding. The Great Mosque of Kairouan (Great Mosque of Sidi-Uqba) is considered as one of the most important monuments of Islamic civilization as well as a worldwide architectural masterpiece. Founded by Arab general Uqba Ibn Nafi in 670 CE, the present aspect of the mosque dates from the 9th century. The Great Mosque of Sidi-Uqba has a great historical importance as the ancestor of all the mosques in the western Islamic world. The Mosque of the Three Gates was founded in 866. Its façade is a notable example of Islamic architecture.