Karachi (Urdu: کراچی; ALA-LC: Karācī, IPA: [kəˈraːtʃi] (About this sound listen); Sindhi: ڪراچي) is the capital of the Pakistani province of Sindh. It is the most populous city in Pakistan, and fourth most populous city proper in the world. Ranked as a beta world city, the city is Pakistan's premier industrial and financial centre. Karachi is also Pakistan's most cosmopolitan city. Situated on the Arabian Sea, Karachi serves as a transport hub, and is home to two of Pakistan's two largest seaports, the Port of Karachi and Port Bin Qasim, as well as the busiest airport in Pakistan.
Though the Karachi region has been inhabited for millennia, the city was founded as the fortified village of Kolachi in 1729. The settlement drastically increased in importance with the arrival of British East India company in the mid 19th century, who not only embarked on major works to transform the city into a major seaport, but also connected it with their extensive railway network. By the time of the Partition of British India, the city was the largest in Sindh with an estimated population of 400,000. Following the independence of Pakistan, the city's population increased dramatically with the arrival of hundreds of thousands of Muslim refugees from India. The city experienced rapid economic growth following independence, attracting migrants from throughout Pakistan and South Asia.
At the dawn of Pakistan's independence in 1947, Karachi was Sindh's largest city with a population of over 400,000. Despite communal violence across India and Pakistan, Karachi remained relatively peaceful compared to cities further north in Punjab. The city became the focus for the resettlement of Muslim Muhajirs migrating from India, leading to a dramatic expansion of the city's population. This migration lasted until the 1960s. This immigration ultimately transformed the city's demographics and economy.
Karachi was selected as the first capital of Pakistan and served as such until the capital was shifted to Rawalpindi in 1958. While foreign embassies shifted away from Karachi, the city is host to numerous consulates and honorary consulates. Between 1958 and 1970, Karachi's role as capital of Sindh was ceased due to the One Unit programme enacted by President Iskander Mirza.
The city's development was largely confined to the area north of the Chinna Creek prior to independence, although the seaside area of Clifton was also developed as a posh locale under the British, and its large bungalows and estates remain some of the city's most desirable properties. The aforementioned historic areas form the oldest portions of Karachi, and contain its most important monuments and government buildings, with the I. I. Chundrigar Road being home to most of Pakistan's banks, including the Habib Bank Plaza which was Pakistan's tallest building from 1963 until the early 2000s.
Situated on a coastal plain northwest of Karachi's historic core lies the sprawling district of Orangi Town. North of the historic core is the largely middle-class district of Nazimabad, and upper-middle class North Nazimabad, which were developed in the 1950s. To the east of the historic core is the area known as Defence – an expansive upscale suburb developed and administered by the Pakistan Army. Karachi's coastal plains along the Arabian Sea south of Clifton were also developed much later as part of the greater Defence Housing Authority project.
Karachi's city limits also include several islands, including Baba and Bhit Islands, Oyster Rocks, and Manora, a former island which is now connected to the mainland by a thin 12 kilometre long shoal known as Sandspit. The city has been described as one divided into sections for those able to afford to live in planned localities with access to urban amenities, and those who live in unplanned communities with inadequate access to such services. Up to 60% of Karachi's residents live in such unplanned communities.
As home to Pakistan's largest ports and a large portion of its manufacturing base, Karachi contributes a large share of Pakistan's collected tax revenue. As most of Pakistan's large multinational corporations are based in Karachi, income taxes are paid in the city even though income may be generated from other parts of the country. As home to the country's two largest ports, Pakistani customs officials collect the bulk of federal duty and tariffs at Karachi's ports, even if those imports are destined for one of Pakistan's other provinces. Approximately 25% of Pakistan's national revenue is generated in Karachi.
According to the Federal Board of Revenue's 2006–2007 year book, tax and customs units in Karachi were responsible for 46.75% of direct taxes, 33.65% of federal excise tax, and 23.38% of domestic sales tax. Karachi accounts for 75.14% of customs duty and 79% of sales tax on imports, and collects 53.38% of the total collections of the Federal Board of Revenue, of which 53.33% are customs duty and sales tax on imports.
Karachi is served by three "Signal-Free Corridors" which are designed as urban express roads to permit traffic to transverse large distances without the need to stop at intersections and stop lights. The first opened in 2007 and connects Shah Faisal Town in eastern Karachi to the industrial-estates in SITE Town 10.5 kilometres (6.5 miles) away. The second corridor connects Surjani Town with Shahrah-e-Faisal over a 19 kilometre span, while the third stretch 28 kilometres (17 miles) and connects Karachi's urban centre to the Gulistan-e-Johar suburb. A fourth corridor is currently under construction that will link Karachi's centre to Karachi's Malir Town.
Karachi will be the terminus of the under construction M-9 motorway, which will connect Karachi to Hyderabad. The road is being constructed as part of a much larger motorway network under construction as part of the expansive China Pakistan Economic Corridor. From Hyderabad, motorways have been built, or are being constructed, to provide high-speed road access to the northern Pakistani cities of Peshawar and Mansehra 1,100 kilometres (680 miles) to the north of Karachi.
Karachi is also the terminus of the N-5 National Highway which connects the city to the historic medieval capital of Sindh, Thatta. It offers further connections to northern Pakistan and the Afghan border near Torkham, as well as the N-25 National Highway which connects the port city to the Afghan border near Quetta.
Within the city of Karachi, the Lyari Expressway is a controlled-access highway along the Lyari River in Karachi, Sindh, Pakistan. As of 8 February 2018 Lyari Expressway's north-bound and south-bound sections are both complete and open for traffic. This toll highway is designed to relieve congestion in the city of Karachi. To the north of Karachi lies the Karachi Northern Bypass (M10), which starts near the junction of the M9. It then continues north for a few kilometres before turning west, where it intersects the N25.
98% of Karachi's households are connected to the city's underground public sewerage system, largely operated by the Karachi Water and Sewerage Board. Households in Orangi Town self-organized in order to set-up their own sewerage system under the Orangi Pilot Project, a community service organization founded in 1980. 90% of Orangi streets are now connected to a sewer system built by local residents under the Orangi Pilot Project. Residents of individual streets bear the cost of sewerage pipes, and provide volunteer labour to lay the pipe. Residents also maintain the sewer pipes, while the city municipal administration has built several primary and secondary pipes for the network. As a result of OPP, 96% of Orangi residents have access to a latrine.
72% reported in 2015 that Karachi's drainage system overflows or backs up, – the highest percentage of all major Pakistani cities. Parts of the city's drainage system overflows on average 2–7 times per month, flooding some city streets.
Karachi has the highest percentage of residents in Pakistan who report that their streets are never cleaned – 42% of residents in Karachi report their streets are never cleaned, compared to 10% of residents in Lahore. Only 17% of Karachi residents reporting daily street cleaning, compared to 45% in Lahore. 69% of Karachi residents rely on private garbage collection services, with only 15% relying on municipal garbage collection services. 57% of Karachi residents in a 2015 survey reported that the state of their neighbourhood's cleanliness was either "bad" or "very bad". compared to 35% in Lahore, and 16% in Multan.