London is the capital and most populous city of England and the United Kingdom. London has a temperate oceanic climate, similar to all of southern England. London is a leading global city in the arts, commerce, education, entertainment, fashion, finance, healthcare, media, professional services, research and development, tourism, and transportation. It is crowned as the world's largest financial center and has the fifth or sixth-largest metropolitan area in the world. It is the world's most-visited city and has the world's largest city airport.