Map - Colombo

Colombo (කොළඹ, ; கொழும்பு, ) is the executive and judicial capital and largest city of Sri Lanka by population. According to the Brookings Institution, the Colombo metropolitan area has a population of 5.6 million, and 752,993 in the Municipality. It is the financial centre of the island and a tourist destination. It is located on the west coast of the island and adjacent to the Greater Colombo area which includes Sri Jayawardenepura Kotte, the legislative capital of Sri Lanka, and Dehiwala-Mount Lavinia. Colombo is often referred to as the capital since Sri Jayawardenepura Kotte is itself within the urban/suburban area of Colombo. It is also the administrative capital of the Western Province and the district capital of Colombo District. Colombo is a busy and vibrant city with a mixture of modern life, colonial buildings and monuments.

Due to its large harbour and its strategic position along the East–West sea trade routes, Colombo was known to ancient traders 2,000 years ago. It was made the capital of the island when Sri Lanka was ceded to the British Empire in 1815, and its status as capital was retained when the nation became independent in 1948. In 1978, when administrative functions were moved to Sri Jayawardenepura Kotte, Colombo was designated as the commercial capital of Sri Lanka.

The name 'Colombo', first introduced by the Portuguese in 1505, is believed to be derived from the classical Sinhala name කොලොන් තොට Kolon thota, meaning "port on the river Kelani".

Another belief is that the name is derived from the Sinhala name කොල-අඹ-තොට Kola-amba-thota which means 'Harbour with leafy/green mango trees'. This coincides with Robert Knox's history of the island while he was a prisoner in Kandy. He writes that "On the West, the City of Columbo, so-called from a Tree the Natives call Ambo, (which bears the Mango-fruit) growing in that place; but this never bear fruit, but only leaves, which in their Language is Cola and thence they called the Tree Colambo: which the Christians in honour of Columbus turned to Columbo."

The author of the oldest Sinhala grammar, Sidatsangarava, written in the 13th century wrote about a category of words that exclusively belonged to early Sinhala. It lists naramba (to see) and kolamba (ford or harbour) as deriving from the indigenous Vedda language. Kolamba may also be the source of the name of the commercial capital Colombo.