Originally, the idea was proposed by Oscar Kittelsen and Sam Eyde in 1913, to bring sunlight to Rjukan, a town hidden in the shadow of surrounding mountains during the winter months.

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This vision became a reality thanks to Martin Andersen, who reintroduced the idea in 2005. In 2013, Tinn municipality constructed the sun mirror, consisting of three heliostats at 742 meters above sea level.

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These mirrors reflect sunlight down onto the square, creating an area bathed in sunlight.