Karachi, city in southern Pakistan, capital of Sindh Province, on the Arabian Sea, at the northwestern edge of the Indus River delta. The hub of a sprawling metropolitan area, Karachi is the nation's largest city and world’s fourth most populated city, spread over, 530 square kilometers. Residents and those born in the city are called "Karachiites". 

Karachi continues to be an important financial and industrial centre for the country and handles most of the overseas trade of Pakistan and the central Asian countries. The Muhammad Ali Jinnah International Airport is the largest and busiest airport of the country. It handles 10 million passengers a year. The Karachi City Station and Karachi Cantonment Station are the city's two major railway stations. 

Karachi was the capital of newly independent Pakistan from 1947 until 1959, when it was replaced by the provisional capital of Rawalpindi (Islamabad became Pakistan's permanent capital in 1967.) The tomb of Muhammad Ali Jinnah, founder of Pakistan, is a landmark. Besides his, the other attractions of the Karachi are Bin Qasim Park ,Mohatta palace Koocha-e-Saqafat (National Arts Council), Masjid e Tooba (Largest single-domed mosque in the world), Seaview, Creek Marina Club ,DA Country Golf club , Area 51 Bowling alley, Pakistan Air Force Museum, Karachi Expo Centre, Karachi Stock Exchange Building, Pakistan Maritime Museum, National Museum of Pakistan, Governor's House, Sindh High Court, Former Victoria Museum (later used by the Supreme Court), National Academy of Performing Arts, Sindbad, Safari Park ,Alladin, Dream World Resort, Boat Basin, Burns Road. Millemium Mall, Park Towers, Dolmen Mall, Naheed Super Market, The Forum, Tariq Road Bazaar, Zamzama Boulevard, Zainab Market,Hyderi Bazaar. 
Located on the coast, Karachi tends to have a relatively mild climate with low levels of average precipitation, the bulk of which occurs during the July-August monsoon season. Winters are mild and the summers are hot, Due to high temperatures during the summer (April to August), the winter months (November to February) are generally considered the best times to visit Karachi. July, December and January have pleasing and cloudy weather when most of the social events take place. 

http://www.youtube.com/watch?v=gzWRhoew2vE