The Qutb Minar was also begun by Qutbu\'d-Din Aibak, in around 1202 and completed by his successor, Muhammad-bin-Sam. It was damaged by lightning in 1326 and again in 1368, and was repaired by the rulers of the day, Muhammad-bin-Tughluq (1325-51) and Firuz Shah Tughluq (1351-88). In 1503 Sikandar Lodi carried out some restoration and enlargement of the upper storeys.