The Great Mosque, the first monument built in the new, Mamluk, Tripoli, remains the largest and best known of the city’s mosques. Officially named the Jami` al-Mansuri al-Kabir after al-Mansur Qala un, who
liberated Tripoli from the Crusaders in 1289, it was erected by his two sons, who had the arcade built around the courtyard in 1314.

Located on the site of what was once a Crusaders` suburb at the foot ofthe Citadel, the Mosque was often mistaken for a remodeled Christian church by medieval travelers and modern historians alike. Two elements, the door and the minaret, probably do belong to an earlier, Christian structure and were incorporated into the mosque when it was built, but the building - its court, arcades, fountain, and prayer hall - is essentially a Muslim creation.

The building has four inscriptions. Two record the date of the construction and the names of its founders. The first, set on the lintel of the main entrance to the mosque, consist of three lines of clearly written naskh.

The Great Mosque occupies en area of about 50 by 60 meters in the middle of the city. It does not have an elaborate facade, but is readily identifiable from the outside by its minaret and its main northern gate, the two controversial elements responsible for the theory that it is a remodeled Christian church.

In the Great Mosque is a traditional arrangement with a central courtyard, single porticoes on three sides, a deeper giblah side for prayer, and a central fountain. In traditional fashion the mosque has three axial entrances set to the north, east and west, but there are also two others on either side of the prayer hall.

A visitor entering the courtyard sees to the right of the main entrance two granite columns springing from the pavement, remnants of classical times that were for some reason left standing. They do not seem to have any practical or decorative function. The courtyard which dominates the building is enclosed by porticoes to the north, east, and west, and by the closed prayer area to the south. The porticoes display a rhythmic arrangement of identical low arches in the courtyard.