EuroVelo 12 (EV12), the North Sea Cycle Route, is a 5,942 km long-distance cycling route circuit around the coastlines of the countries that border the North Sea: these countries are (going clockwise from an arbitrary starting point of Harwich in Essex) England, Scotland, Norway, Sweden, Denmark, Germany, the Netherlands, and Belgium.

The North Sea Cycle Route was officially opened in 2001 and is an international project between the countries participating, with 68 partners in 8 countries. This is the world’s longest cycle route, covering a distance of around 6,000 km.

According to Wikipedia