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In the base of a valley: A town that uses mirrors for sunlight

06:12 PM
December 7, 2025

In the base of a valley
A town that uses mirrors for sunlight

A large mirror on the side of a mountain reflected sunlight towards a town in darkness due to its location within a valley.Giant mirrors reflect sunlight towards the dark town of Rjukan. - © picture alliance

The days may be getting shorter, but at least we get natural sunlight, unlike a town in Norway that relies on mirrors to bring the sunshine.

Located at the bottom of a steep valley surrounded by mountains, the tiny town of Rjukan does not see sunlight for seven months of the year. Rjukan was built between 1905 and 1906 by Sam Eyde. It was Eyde who dreamt of a giant mirror in 1913 to provide sunlight for the town's factory workers, though it took until 2013 that it became a reality.

Three 182-square-foot mirrors controlled by computer-driven motors were installed to bring a 6,500 square-foot area of winter sunshine to the town.

The mirrors are able to bring 80-100 percent of the sun’s light to Rjukan by tracking the movement of the sun and repositioning themselves every 10 seconds to keep the light consistent.

Sunshine hours

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Although the mirrors are unique, Rjukan’s were not the first. In December 2006, the town of Viganella in Italy’s Antrona Valley celebrated a day of light after a steel sheet was installed to reflect sunlight between November and February.

Becca Parker
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