Rjukan–Notodden Industrial Heritage Site

The Rjukan–Notodden Industrial Heritage Site is a World Heritage Site in Telemark county, Norway, created to protect the industrial landscape around Lake Heddalsvatnet and Vestfjorddalen valley. The landscape is centered on the plant built by the Norsk Hydro company to produce calcium nitrate fertilizer from atmospheric nitrogen using the Birkeland–Eyde process. The complex also includes hydroelectric power plants, railways, transmission lines, factories, and workers' accommodation and social institutions in the towns of Notodden and Rjukan. This site, along with the Odda–Tyssedal Industrial Heritage Site, was placed on the tentative World Heritage list on 19 June 2009. On 5 July 2015, it was placed on the World Heritage list under Criteria II and IV with the following description of the Outstanding Universal Value: