Karachi - the noisy, bustling, ever-growing troubled metropolis of Pakistan, lies on the eastern coast of the Arabian Sea, just northwest of the Indus river delta. The largest city, and unarguably the most important, Karachi was the original capital of the nation. It is the 7th largest urban agglomeration in the world, and the second largest in the Muslim world. It is Pakistan's centre of banking, industry, economic activity and trade and is home to Pakistan's largest corporations, including those involved in textiles, shipping, automotive industry, entertainment, the arts, fashion, advertising, publishing, software development and medical research. The city is a hub of higher education in South Asia and the Muslim world. It is also ranked as a beta world city.