The Quwwat-ul-Islam Masjid can be a bewildering experience for those unfamiliar with its history. On one hand there is the beautiful, curvaceous Islamic calligraphy, the arabesque designs and then there are pillars with clearly pre-Islamic Hindu motifs. The reason is of course quite simple; the pillars were taken from the 27 temples of Qila Rai Pithora, the city of the Rajput king Prithviraj Chauhan (see history). This in fact has been recorded by Qutub-ud-din in his inscriptions, who calls it the Jami Masjid (Friday Mosque) in his inscriptions.

OThe mosque was started in 1192 by Qutub-ud-din Aibak, the first ruler of the Slave Dynasty (called so because the founder was once a royal slave). It was finished four years later. However the masjid, much like the Qutub complex itself, never stopped growing and many subsequent rulers, like Altamash in 1230 and Alauddin Khalji in 1315, added their own bits to it. As soon as you passing through the entrance (watch out for the steep steps) of the poetically beautiful Quwwat-ul-Islam mosque the intricately carved temple ceiling catches your eye. In front of you will be the spectacular courtyard of the mosque which is lined by the rows of the profusely adorned pillars talked about earlier on both sides. Hindu motifs, like tasseled ropes, bells, tendrils, cows and leaves, frolic all over the mosque. The very first indication of the Islamic character of the building come from the elegant pointed arches with curvaceous and serpentine calligraphy of texts from Quran in Arabic crowning them, towards the west of the mosque. A massive stone screen was erected in front of the prayer hall, with a central arch and two similar, though smaller, arches on either side; all of these are shaped like an 'S' (ogee-shaped). The prayer hall of the mosque stands to the west. It consists of a central arch which is over 6.15m (20ft) high and profusely carved, crowded with exquisite decorations and is one of the earliest and finest examples of the fusion of Hindu and Islamic art.

Later Qutub-ud-din's son-in-law and successor, Altamash had the prayer hall screen extended, and added three more arches besides the original five. The difference between the two arches is interesting: the earlier arches are not really the 'true' arch which is such a hallmark of Islamic architecture, Altamash's arches were built by workmen from Afghanistan and are stylistically quite distinct. They use Islamic motifs such as geometrical shapes rather than naturalistic designs (which were frowned upon by the Muslim clergy) that Hindus used. Ala-ud-din Khalji added a courtyard to the mosquethe entrance to which is the amazing Alai Darwaza. In the mosque compound is the small but pretty tomb of Imam Zamim, who was the Imam (head priest) of the mosque during Sikander Lodi's (1488-1517) reign.