🇬🇧 United Kingdom
London
London (population 9.7 million Greater London; 14+ million metropolitan area) is the capital of the United Kingdom and the largest city in Western Europe — a city on the Thames Estuary that has been continuously inhabited for 2,000 years since the Romans founded Londinium in 43 CE. London is simultaneously the world's leading financial centre (the City of London — the 'Square Mile'), the most-visited city in the world (21+ million international visitors/year), and a city of extraordinary cultural density: the British Museum (8 million artifacts; the Rosetta Stone, the Elgin Marbles, the Lewis Chessmen), the National Gallery (the finest collection of pre-20th-century European painting in any single building), the Tate Modern (the world's most-visited modern art museum), the V&A, the Natural History Museum, and dozens more are all free. Westminster (the Houses of Parliament, Westminster Abbey, Buckingham Palace), the City of London (St Paul's Cathedral, the Tower of London, the Gherkin), and East London (Brick Lane, Shoreditch, the Barbican) represent three utterly different faces of the same city. The London transport system (the Tube — opened January 10, 1863; the world's first underground railway) covers 402km of track across 11 lines and 272 stations. The Thames (the 'liquid history' in Winston Churchill's phrase) divides the city into north (the historic, museum-dense north bank) and south (the Tate Modern, the Shard, Brixton). Three days cannot contain London — but they can capture its essential character. Best months: May–September (though London is worth visiting any month).