India houses numerous mosques named as Jama Masjids. Among these the largest one is in Delhi. Mumbai also has one Jama Masjid of great distinction. The Jama Masjid of Mumbai has changed its location more than once in its years of existence. The original Jama Masjid of Mumbai was situated near Dongri. It was later removed and erected at Esplanade. In 1770, this mosque too was demolished by an order of Governor William Hornby which forbade the existence of any building within 600 years of the walls of the Fort. The construction of the present Jama Masjid started in 1775. After 33 years of labour only first storey of the mosque was complete. The upper storey was added in 1837. but work on it could not be completed till 1802. The Masjid is a quadrangular pile of brick and stone encircled by a ring of terraced roofed and double storied buildings. The main eastern gate leads to an ancient tank filled with about 10 feet of water. From the depths of the tank rise 16 black stone arches which support the whole of the mosque.