Rjukan–Notodden Industrial Heritage Site is created to protect the industrial landscape around Lake Heddalsvatnet. The landscape is centered around the plant built by the Norsk Hydro to produce fertilizer from atmospheric nitrogen. The complex also includes hydroelectric power plants, transport systems, including railways, transmission lines and factories, and workers' accomodation and social institutions in the towns of Notodden and Rjukan.
In the 1900s, Norway experienced rapid industrial development through the availability of cheap hydroelectric power. Kristian Birkeland developed a method to extract nitrogen from the air, which, after an initial trial in Notodden in 1907, looked superior to existing technologies. Nitrogen was needed to produce fertilizers. Norsk Hydro was founded in 1905, and industrial development began in the Eastern Telemark region, previously an underdeveloped and underpopulated agricultural area. To produce fertilizers, it was essential to build factories, power stations, infrastructure for workers, as well as facilities for exporting the production. The fertilizers, artificial salpetre, eventually surpasses the Chilean naturally mined salpeter, at the time the most widely used fertilizer.
At the beginning of construction, in 1907, the power was provided by the Svelgfoss Hydroelectric Power Station, which at the time was the largest in Europe and the second larges at the world. The station is still in operation. Subsequently, two more station were built. Vemork, built on a waterfall near Rjukan, in 1911 was the largest power station in the world. A plant producing heavy water and most famous for the 1943 sabotage events (Operation Gunnerside) was built nearby. The original building of the station has been destroyed, but the station is in operation. Another power plant, Såheim Hydroelectric Power Station, started operation in Rjukan in 1915. The building survived but the station operates elsewhere.
One of the 36 towers of the salpetre factory's towerhouse, which was in operation between 1911 and the 1980s, has been conserved and is protected as a cultural monument.
In 1925, 80% of all apartments in Rjukan (1230 in total) were controlled by the Norsk Hydro. red brick apartment buildings dominated, others were houses with individual gardens.
The site was placed on the tentative World Heritage list on 26 November 2011 together with the Odda–Tyssedal Industrial Heritage Site. In 2015 it was placed on the World Heritage list.
References:The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.