In common with many ski areas up in northern Scandinavia, Finland's largest ski area, Levi, has entered a period of 'Polar night' during which the sun does not rise above the horizon.
The sun set yesterday and will not reappear above the horizon until 12.16 on New Year's Day. The period is known as 'Kaamos' in the region.
The ski slopes, which are normally floodlit anyway, remain open and there is some daylight, coming from just below the horizon, through the three week period.
Along with floodlit downhill ski slopes there are 28 km of illuminated cross country ski trails and another 25 km of floodlit winter hiking and biking routes. Lighting is on from 6am to 11pm daily.
Levi is already into the third month of its 7-month long 23-24 season, which began in early October.