Qutub Minar, the tallest stone tower in India was conceived by Qutub-Din Aibak (A.D. 1192-1210) as a tower of victory attached to Quwwat-ul-Islam Mosque. Qutub-Din completed the first storey while the second, third, fourth were completed by his successor Iltutmish (A.D. 1211-1236). When it was damaged by lighting in 1326 and 1368, The fourth storey was dismantled and reconstructed by Firuz Tughluq
(A.D. 1351-1388) with an additional storey, making it a five storied structure.