The Federal District (Portuguese: Distrito Federal; Portuguese pronunciation: [dʒisˈtɾitu fedeˈɾaw]) is one of 27 federative units of Brazil. Located in the Central Plateau of the Brazilian Highlands, the Federal District is divided into 31 administrative regions, and contains the Brazilian capital city, Brasília, which is also the seat of government of the Federal District. The capital — the seat of the three branches of the federal government of Brazil (legislative, executive and the judiciary) — is the main attraction of this dry area, whose climate has only two seasons. During the dry season (winter), the humidity can reach critical levels, mainly in the peak hours of the hottest days. The artificial Paranoá Lake, with almost 40 km² (15 sq mi) and 500 million cubic metres (410,000 acre·ft) of water, was built to minimize the severe dry, climatic conditions of winter in the Cerrado vegetation.

The capital of Brazil was transferred from Rio de Janeiro to Brasília on 21 April 1960 and its new territory was split off from Goiás. After the transfer the old Federal District (1891-1960) became Guanabara state, the only city-state Brazil ever had so far. This existed from 1960 until 1975 when it merged with Rio de Janeiro state. With the merge, the capital was transferred back from Niterói to Rio de Janeiro, as it was until 1834 when the empire created the Neutral Municipality.

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