Denmark's answer to a chalk stream — spring-fed, crystal clear, with wild brown trout and sea trout that behave like educated Hampshire fish. The water quality is exceptional and the trout know it: they feed selectively, inspect your fly with irritating thoroughness, and refuse anything that doesn't convince them completely. Premium water with restricted access — guided days or private invitation. If you want to test your dry fly skills against properly difficult fish in a Scandinavian setting, this is the river.

• Limestone