Home / Editor's Pick /

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

18:00
24 November 2024

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% 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

Track sunshine hours near you with daily sunrise and sunset times in the astro card. 

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.

Why do the clocks change?read more
Ryan Hathaway
More on the topic
Split image showing an alpine winter landscape and a European weather map with snow and rain areas.
Monday 1 December 2025

Winter begins today

Wintry weather only in a few places
The image shows the ruins of a house on the left and the weather radar with thunderstorms over Sumatra on the right.
Wednesday 3 December 2025

Heavy monsoon rain

Flood disaster on Sumatra
Weather radar map of the UK and Ireland showing widespread blue precipitation bands with temperatures near major cities, overlaid by a large cloud with two blue raindrops.
Tuesday 2 December 2025

Close to record-breaking

A wet autumn season in the books
All weather news
This might also interest you
Split weather map showing the UK and Ireland. The left side illustrates strong winds circulating around a low-pressure system, with gusts of 20–30 mph highlighted in orange and yellow. The right side shows radar imagery with widespread blue rain bands and patches of thunderstorms, especially over northern England and Scotland.
Thursday 28 August 2025

Breakfast brief

Remaining widely unsettled
Weather map of the UK and Ireland showing scattered showers with cloudy patches across much of the region, especially around western and northern areas. Sunshine symbols appear over London, Cardiff, and parts of southern England, while temperatures range from 17°C to 18°C in most places. Areas of heavier rain are visible over the Atlantic to the west.
Friday 29 August 2025

Breakfast brief

Unsettled conditions into the weekend
Split weather map showing UK wind speeds in orange-red shades up to 40 mph on the left and warning levels in green-yellow on the right, with a central wind warning sign.
Wednesday 22 October 2025

Warnings active

Storm Benjamin impacts the UK
All articles
Weather & Radar

Weather & Radar is also available on

Google Play StoreApp Store

Company

Contact us Privacy Policy Legal info Accessibility statement

Services

Uploader

Socials

facebooktwitteryouTubelinkList