Nairobi is the capital and largest city and County in Kenya. The name "Nairobi" comes from one of the Kenyan community the Maasai phrase Enkare Nyirobi, which translates to "the place of cool waters". However, it is popularly known as the "Green City in the Sun" and is surrounded by several expanding villa suburbs. Founded in 1899 as a simple rail depot on the railway linking Mombasa to Uganda, the town quickly grew to become the capital of British, East Africa in 1907 and eventually the capital of a free Kenyan republic in 1963. During Kenya's colonial period, the city became a centre for the colony's coffee, tea and sisal industry. The city lies on the Nairobi River and has an elevation of 1795m above sea-level. Nairobi is the most populous city in East Africa, with a current estimated population of about 3 million. According to the 2009 Census, in the administrative area of Nairobi, 2,143,254 inhabitants lived within 696 km2 (269 sq mi).Nairobi is currently the 13th largest city in Africa, based on population and fourth largest in infrastructure development and its size. The City is now one of the most prominent cities in Africa politically and economically.

It is a home to many multi-national companies such as Toyota Africa, Coca Cola Africa, and International organizations, including the United Nations Environment Programme UNEP and the UN Habitat Office in Africa; Nairobi is established as a hub for business and culture. The Nairobi Stock Exchange (NSE) is one of the largest in Africa, ranked fourth in terms of trading volume and capable of making 10 million trades a day. The Globalization and World Cities Study Group and Network (GaWC) defines Nairobi as a prominent socio–economic centre.

The city serves the region economically as a connection hub with the Main airport Jomo Kenyatta International Airport (JKIA) , the biggest Airport in East and Central Africa. JKIA is the focal point for major aviation activity in the region. Its importance as an aviation centre makes it the pacesetter for other airports in the region. JKIA, located 18 kilometers to the East of Nairobi,is served by 49 scheduled airlines. JKIA has direct flight connections to Europe, the Middle East, Far East and the African Continent