The city

Rjukan gained a railway connection in 1909 with Norway's first standard-gauge private railway, the Rjukan Line (originally named the Vestfjorddalen Line), which was officially opened by King Haakon VII on August 10, 1909. On May 17, 1914, "the labor movement held an anti-militarist demonstration that ended in a scuffle when the police attempted to prevent the demonstrators from marching in the streets. Among the emblems they marched under was 'the broken rifle' —a symbol that had been banned in March of that same year. The 'incident' became a matter for the Storting, and in the autumn, around 15 workers were sentenced to fines or imprisonment." Rjukan was formerly a major industrial center in Telemark with over 12,000 inhabitants, developed around Norsk Hydro's establishment of the "Rjukan Saltpeter Factories" in the early 20th century. The town took its name from the Rjukanfossen waterfall, following an internal naming competition. Originally, the place was called Saaheim, which was also a potential name for the town. Norsk Hydro's establishment was driven primarily by the abundant supply of electric power made available through the regulation of the Måna River and its main source, Lake Møsvatn. The engineer and industrial entrepreneur Sam Eyde (1866–1940) is considered Rjukan's founder and is commemorated by a bronze statue in Rjukan Town Square. He established the Norwegian nitrogen industry (artificial fertilizer production) based on Kristian Birkeland's method, developed hydroelectric power at sites such as the Rjukan and Svelgfoss waterfalls, and thereby created the industrial towns of Rjukan and Notodden. In 1928, Norsk Hydro built a Hydrogenfactory at Vemork. And in 1934 they started world's first commercial heavy water plant at Vemork in Rjukan.  The plant was operated by the Germans in conjunction with Norsk Hydro during World War II and was subsequently sabotaged several times by Allied forces. See the separate article on the Vemork raid. Today, the power station has been converted into the Norwegian Industrial Workers Museum, which recounts the history of Rjukan and its industrial workforce, as well as the wartime and sabotage history associated with the site. After 1960, most of the saltpeter production at Rjukan was transferred to Hydro's manufacturing complex at Herøya in Porsgrunn. Some industry remains in Rjukan, including companies such as BILFINGER  HYDRO ENERGI and NIPPON GASES. And some new industries have come, such as HIMA SEAFOOD and GREEN MOUNTAIN. Rjukan was also home to Telemark's first vehicle powered by a gas generator; it arrived as early as June 1940. The generator unit was purchased by Tinn Municipality and mounted on a bus belonging to Tinn Billag. The bus operated on the route between Tessungdalen, Austbygda, and Rjukan. The generator was supplied by Strømmen Verksted.

UNESCO World Heritage List On July 5, 2015, 

Rjukan was inscribed on the UNESCO World Heritage List — together with Notodden — as the Rjukan-Notodden Industrial Heritage Site, recognized for its outstanding universal value. In 2009, Rjukan was placed on Norway's tentative list for UNESCO World Heritage status, alongside Notodden, as well as Odda and Tyssedal.  In January 2013, the Ministry of the Environment decided to split the nomination into two phases: the first application, covering Rjukan and Notodden, was to be submitted to UNESCO in January 2014; a second phase involved further work on expanding the nomination to include Odda and Tyssedal, with a potential submission to UNESCO in January 2016 — a plan that ultimately did not materialize. The application was submitted to UNESCO in January 2014. It proposed listing Rjukan and Notodden as outstanding representatives of the Second Industrial Revolution, with the nomination comprising four components: industry, hydroelectric power, transport systems, and factory towns. The application was reviewed and approved by ICOMOS — UNESCO's advisory body — on May 15, 2015. A final decision regarding its inscription on the UNESCO World Heritage List was reached in Bonn on July 5, 2015 — 108 years and one day after Sam Eyde decided to build the town of Rjukan. The Rjukan-Notodden Industrial Heritage Site was inscribed under criteria II and IV, based on the following outstanding universal value.

"Located in a dramatic landscape of mountains, waterfalls and river valleys, the site comprises hydroelectric power plants, transmission lines, factories, transport systems and towns. The complex was established by the Norsk-Hydro Company to manufacture artificial fertilizer from nitrogen in the air. It was built to meet the Western world's growing demand for agricultural production in the early 20th century. The company towns of Rjukan and Notodden show workers' accommodation and social institutions linked by rail and ferry to ports where the fertilizer was loaded. The Rjukan-Notodden site manifests an exceptional combination of industrial assets and themes associated to the natural landscape. It stands out as an example of a new global industry in the early 20th century."