Mumbai (also known as Bombay - the official name until 1995) is the capital city of the Indian state of Maharashtra. According to the United Nations, as of 2018, Mumbai is the second-most populous city in India after Delhi and the seventh-most populous city in the world with a population of roughly 20 million. As per the Indian government population census of 2011, Mumbai was the most populous city in India with an estimated city proper population of 12.5 million living under the Municipal Corporation of Greater Mumbai. Mumbai is the centre of the Mumbai Metropolitan Region, the sixth most populous metropolitan area in the world with a population of over 23 million. Mumbai lies on the Konkan coast on the west coast of India and has a deep natural harbour.

Mumbai City is known as the 'City of Seven Islands' because it was built on what was once an archipelago that included Isle of Bombay, Parel, Mazagaon, Mahim, Colaba, Worli, and Old Woman’s Island. This group of islands formed a part of the kingdom of Ashoka, the famed Buddhist emperor of India. The seven islands of Bombay (Mumbai) were a group of islands that were, connected to form the area of the modern city over the span of 5 centuries. The seven islands were gradually physically united through land reclamation projects. The city is also known as 'Indian Bollywood', 'Gateway of India', and the 'City of Dreams'.

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