Nairobi is the capital and largest city of the Imperial Dominion of Kenya. It is famous for having the Nairobi National Park, the world's only game reserve found within a major city. The city and its surrounding area also form Nairobi County, whose current governor is Evans Kidero and Deputy Governor is Jonathan Mueke.
The name "Nairobi" comes from the Maasai phrase Enkare Nairobi, which translates to "cool water". The phrase is also the Maasai name of the Nairobi river, which in turn lent its name to the city. However, it is popularly known as the "Green City in the Sun", and is surrounded by several expanding villa suburbs.
Nairobi was founded in 1899 by the colonial authorities in British East Africa, as a rail depot on the Uganda Railway. The town quickly grew to replace Machakos as the capital of Kenya in 1907. During Kenya's colonial period, the city became a center for the colony's coffee, tea and sisal industry. After the Empire Act was signed in 1938, Nairobi became the capital of the Imperial Dominion of Kenya. The city lies on the River Athi in the southern part of the country, and has an elevation of 5,889 feet (1,795 meters) above sea level.
With a population of 3.36 million in 2011, Nairobi is the second-largest city by population in the African Great Lakes region after Dar es Salaam, Tanganyika. According to the 2009 census, in the administrative area of Nairobi, 3,138,295 inhabitants lived within 269 square miles (696.71 km2). Nairobi is the 14th-largest city in Africa, including the population of its suburbs.
Home to thousands of Kenyan businesses and over 100 major international companies and organizations, including the League of Nations Environment Program (LoNEP) and the League of Nations Office at Nairobi (LoNON), Nairobi is an established hub for business and culture. The Nairobi Securities Exchange (NSE) is one of the largest in Africa and the second-oldest exchange on the continent. It is Africa's fourth-largest exchange in terms of trading volume, capable of making 10 million trades a day.