Abu Dhabi is the capital of, and the second largest city in the United Arab Emirates. Abu Dhabi lies on a T-shaped island jutting into the Persian Gulf from the central western coast. The city proper, making up an area of 67,340 km2 (26,000 sq mi), had an estimated population of 860,000 in 2008. Abu Dhabi houses important offices of the federal government, and is the seat for the United Arab Emirates Government and the home for the Emirati Royal Family. Abu Dhabi has grown to be a cosmopolitan metropolis. Its rapid development and urbanisation, coupled with the relatively high average income of its population, has transformed Abu Dhabi, making the city more advanced than most other Arab cities. Today the city is the country's center of political, industrial activities, and a major cultural, and commercial centre due to its position as the capital. Abu Dhabi alone generated 56.7% of the GDP of the United Arab Emirates in 2008. Abu Dhabi is home to important financial institutions such as the Abu Dhabi Securities Exchange, the Central Bank of the United Arab Emirates and the corporate headquarters of many companies and numerous multinational corporations. One of the world's largest producers of oil, Abu Dhabi has actively attempted to diversify its economy in recent years through investments in financial services and tourism. Abu Dhabi is the third most expensive city in the region, and 26th most expensive city in the world. Fortune stated in 2007 that Abu Dhabi was the richest city in the world. ( source Wikipedia )