Purana Qila was built on the banks of River Yamuna. The Yamuna was an important element in many of the older cities. It not only brought down the summer heat, but the dry riverbed also provided a venue for elephant fights, and a gathering space from where the populace could see their emperor. The river was also important in terms of defense. By the end of the 19th century, however, the Yamuna had started shifting to the east, and it no longer washed the walls of the fort, nor did it provide a scenic view of a riverside fort, a popular subject with tourists.The Qila-i-Kuhna, or Sher Shah’s royal chapel, which was built around 1540, was a fairly small building with a 170 feet wide façade. In the arcade of five archways with ‘true’ horseshoe-shaped arches, the red and yellow sandstones look beautiful with white marble insets. The narrow turrets on each corner of the back wall, and the fluted moulding associated with the Qutub Minar are all beautiful.The prayer hall of 51.20m by 14.90m – with five elegant mihrabs set in the western wall and calligraphic inscription in red, white, and slate marble on the central iwan – marks a transition from Lodhi to Mughal architecture. At one time, the courtyard had a shallow tank, with a fountain. A second storey, accessed through staircases from the prayer hall, with a narrow passage running along the rectangular hall, provided space for female courtiers to pray. A marble slab within the mosque reads: ‘As long as there are people on the earth, may this edifice be frequented and people be happy and cheerful in it’. The architecture style and aesthetics of Qila-i-Kuhna could be seen as the crystallization of forms and experiences, which were being developed in a series of small mosque structures, such as the mosque attached to the Bara Gumbad (1495), the Moth ki Masjid (1505) and the Jamali Kamali Mosque (1536), constructed prior to Qila-i-Kuhna. QILA-I-KUHNA MOSQUE, PURANA QILA, NEW DELHIThought by ILF Expert Mantasha Kalam