The Emirate of Abu Dhabi is the largest of the seven emirates, and its main city - Abu Dhabi - is the capital of the UAE. It has an area of 87,340 square kilometers equivalent to 86.7% of the country's total area, excluding the islands. The estimated population of the emirate is 841,000 (1992)   

The Emirate of Abu Dhabi is comprised of three major regions:   
The Abu Dhabi region, which includes the city of of Abu Dhabi. It is the headquarters for the president of the state, the cabinet and most of the ministries, the Federal institutions, foreign embassies, broadcast television, Zayed Port, Abu Dhabi Airport, and most of the oil companies.   
The Eastern region, with its capital Al-Ain City. This region is very fertile and rich in greenery, with plenty of farms and public parks. This region is also very rich in ground water, with numerous artesian wells. The most attractive landmarks in this region are Ain-Faydah Parks, Hafeet Mountain, Al-Heili Leisureland, the Zoo, and Al-Ain Museum. It has has the most admired cultural landmark: The UAE University.   
The Western region's capital city is Beda-Zayed. It has a wide stretch of grown forests to combat the desert climate. Its current area is about 100,000 hectares containing about 20 million green trees. Certain on-shore oil fields are located in this region. The largest oil refinery in the country is located in this region at Al-Ruwais City.   

A number of islands are part of this Emirate. The most significant in this chain are Das Island, Mubraz Island, Zirku Island, and Arzana Island, which constitute the main off-shore oil fields. Other islands include Al-Sadyaat and Abu El-Abyaadh.(from…http://www.uae.org.ae/Map/ummalquwain.html).