The mausoleum of Muhammad Ali Jinnah, principal founder of modern Pakistan, stands in calm contrast to teeming Karachi. Once the capital and still the nation's largest city, it has absorbed Muslim immigrants from around the region—from India, Afghanistan, and from other regions of Pakistan. Some 300,000 arrive yearly to an already crowded city swept by ethnic feuds, corruption, and terrorist acts. Still, the city remains important as a center for transportation and commerce.