Hoorn [ˈɦɔːrn] ( listen) is a municipality and a town in the Netherlands, in the province of North Holland. It is located on the IJsselmeer, 35 kilometres north of Amsterdam, and acquired city rights in 1357. Hoorn has 70,196 inhabitants (CBS: 3 March 2010). The area of the municipality is 52.49 km² (32.62 km² consists of water, mainly the Markermeer), and consists of the following villages and/or districts: Blokker, Hoorn, Zwaag, and parts of Bangert and De Hulk.

Cape Horn, the most southerly point of the Americas, was named after the town by Willem Schouten, who rounded it in 1616.

The origin of the name Hoorn - even in old spelling Hoern(e) or Hoirne - is surrounded in myths. Hoorn's name, according to Old Frisian legends is derived from the stepson of King Redbad (Radboud), called Hornus. Other stories about the origin of the name is derived from a sign depicting a post horn in early 14th century hanging outside one of the establishments situated on the Roode Steen Square. A third version says that the name was derived from the horn shape of one of its first ports. The author of the 'Origo Civitatis Hornensis' (see page. 256, 'Uit de schemer van Hoorns verleden') assumes that name Hoorn was derived from Damphoorn. Damphoorn is the medieval name for a weed that could be made into whistles, which grew in abundance in the area outside the dykes of Hoorn. Chronicler Velius rejects this statement because there are no old historical entries that Hoorn was called Damphoorn. He wrote: The name was from the start Hoorn: not (against better judgement) derived from the weed Damphoorn, if t'ghemeyne ghevoelen van noch heden hout (De name was van eersten af Hoorn: niet (behoudens beter oordeel) van het kruyt Damphoorn, als t'ghemeyne ghevoelen van noch heden hout). Velius also rejects the assertion that the name origin Dampter Horn: a neighbourhood of the village Dampten, which flooded and had fallen into disuse.

Mike van der Hoorn (born 15 October 1992) in the Netherlands is a Dutch football (soccer) player who plays as a Center back. He currently plays for FC Utrecht in the Eredivisie.