In the north of Norway, in a deep valley between towering mountains, lies a small town, home to 3,000 people, that is plunged into darkness and receives no direct sunlight for six months of the year.
This is because the low sun is blocked by the tall Gaustatoppen mountain to the south of Rjukan.
So, in 2013, an art project – at a cost of five million kr (just under £357,000) – was installed on the northern mountainside above the town to fix the issue and provide its residents with some much-needed Vitamin D.
Finally pulled from the darkness, sunlight now illuminates a small portion of the town – three hours northwest of Oslo – each day.
In 1906, the area which would become Rjukan consisted of just a handful of farms, but the site was chosen because of the Rjukan Falls, with a 104-metre waterfall which provided easy means of generating large amounts of electricity.
At the time of its construction, the Vemork hydroelectric power plant was the largest in the world.
Alongside the factories, many houses for the factory workers also had to be built, as well as a train station and town hall. By 1920 its population had reached 8,350.
But, its inhabitants have to spend the months of September through the March in complete darkness.
To fix this problem, three large solar-powered, computer-controlled mirrors were installed 450 metres above the town in 2013 to track the Sun’s movements and reflect its rays down on the square.
Speaking to The Guardian in 2013, retired secretary, Ingrid Sparbo, said people “do sort of get used to the shade. You end up not thinking about it, really.”
But, when she saw the sunlight radiating into the square, she said in disbelief: “It’s the Sun!” lifting her face and closing her eyes to the glare she was not used to. “This is so warming. Not just physically, but mentally. It’s mentally warming.”
Electrical engineer Eivind Toreid added: “It’s a funny thing. Not real sunlight, but very like it. Like a spotlight.”
He said living in Rjukan during the autumn in the weeks before the Sun comes back are the worst: “You look just a short way up the mountainside and the sun is right there, so close you can almost touch it. But not here.”
Beyond this impressive project, Rjukan is also well known for the heavy water sabotage operations at the Vmork plant during World War Two. On November 16 and 18, 35 US heavy bombers extensively attacked the station for over nine hours.
Eventually, the Germans decided to abandon the plant and move its remaining stocks to Germany in 1944.