The city of Kairouan is generally regarded as the 4th holiest city in Islam (after Mecca, Medina, and Jerusalem). The Great Mosque of Kairouan was the first Muslim place of prayer in North Africa and remains an important pilgrimage destination today. Kairouan is also the oldest Muslim city in the Maghreb.
Kairouan was founded in 670 as a military outpost but was resettled in 694 as an important center for Sunni Islamic scholarship and Quranic learning. This religious center served as a pillar for orthodox Islam standing against both non-Muslim infidels and heretical forms of Islam. It was cut off from the surrounding Christian and Jewish populations, which had not yet diminished at that time. Only Muslims were permitted entry inside the city walls until modern times. Kairouan has been a UNESCO World Heritage Site since 1988.
The most important site in Kairouan is the Great Mosque of Okba, which dates to around AD800. There is a large courtyard with pillars surrounding the minaret and prayer area. This mosque may be visited by non-Muslims, but they are prohibited from entering the prayer area.
A visit to Kairouan would not be complete without exploring the UNESCO world heritage site of the Ancient Medina. As you travel here, you will enjoy the narrow streets, colorful shops, and many monuments important to Muslims.