Amsterdam is the capital and most populous city of the Netherlands with a population of 872,680 within the city proper, 1,380,872 in the urban area and 2,410,960 in the metropolitan area. Found within the province of North Holland, Amsterdam is colloquially referred to as the "Venice of the North", attributed by the large number of canals which form a UNESCO World Heritage Site.
Amsterdam's name derives from Amstelredamme, indicative of the city's origin around a dam in the river Amstel. Originating as a small fishing village in the late 12th century, Amsterdam became one of the most important ports in the world in the Dutch Golden Age of the 17th century and became the leading centre for finance and trade. In the 19th and 20th centuries, the city expanded, and many new neighbourhoods and suburbs were planned and built. The 17th-century canals of Amsterdam and the 19–20th century Defence Line of Amsterdam are on the UNESCO World Heritage List. Sloten, annexed in 1921 by the municipality of Amsterdam, is the oldest part of the city, dating to the 9th century.