Mumbai acquired its port importance only with the advent of the Portuguese in 1508. Francis Almeida sailed into this harbour and called it as Bom Bahia or the Good Bay. The British corrupted the Portuguese name “Bom Baia” to “Bombay”. The Kolis used to call the islands “Mumba” after Mumbadevi.
It was the British who developed it into a centre of commerce to rival any other centres in the country then. The British embarked upon large-scale reclamations and engineering works to consolidate the seven islands. In 1803 Bombay was connected with Salsette by a causeway at Sion. A causeway now called Colaba Causeway joined the island of Colaba to Bombay in 1838 and the Causeway connecting Mahim and Bandra was completed in 1845. This gave access to the rich hinterland of the Deccan providing further impetus for the growth of then Bombay.