Kristiansund (USˈkrɪstʃənsʌnd,_ˈkrɪstiənsʊn, krɪstjɑnˈsʉnː; historically spelled Christianssund and earlier named Fosna) is a town in Kristiansund Municipality in Møre og Romsdal county, Norway. The town is the administrative centre of the municipality. it is located on the islands of Kirkelandet, Innlandet, and Nordlandet in the Nordmøre region of the county. The town has a population (2018) of 18,292 and a population density of . Kristiansund is one of the most densely populated cities of Norway, having what is arguably the country's most urban small city centre, due to the relatively small size of the islands on which it is built and the very constricted central harbour/town area of Kirkelandet. The town, formerly spelled Christianssund, was named after the Danish-Norwegian King Christian VI in 1742. The last element of the name, sund, means "strait". The old name of the town/village (originally the island Kirkelandet) was Fosna or Fosen (fólgsn) which means "hiding place" (here 'hidden port'). It was also often named Lille Fosen ("the small Fosen") to distinguish it from the island Storfosna ("the big Fosen") in Ørland to the north. Before 1877, the name was written Christianssund, from 1877 to 1888 it was spelled Kristianssund, and since 1889 it has had its present spelling, Kristiansund. Before the introduction of postal codes in Norway in 1968, it was easy to confuse the name Kristiansund with Kristiansand in the south. It was therefore obligatory to always add an N (for north) to Kristiansund (Kristiansund N) and an S (for south) to Kristiansand (Kristiansand S). This is pretty much still practiced and also occurs in some other contexts than postal addresses. The coat of arms was granted on 27 June 1742. The arms were granted by King Christian VI and are described as a silver or white river flowing from a cliff, with salmon jumping upwards on a blue background. The waterfall may possibly be the Lille Fosen waterfall near the town. There are two myths as to why the arms show a waterfall.