Officially the first day of winter, the winter solstice occurs when the North Pole is tilted 23.5 degrees away from the sun.
The event will occur on Wednesday 21 December this year.
It is the longest night of the year, meaning the days will get progressively longer and lighter as we approach the summer solstice in 2017.
During the winter solstice the sun is closer to the horizon than any other time of the year.
Winter solstice is celebrated by many as the beginning of the return of the sun, darkness turning into light, birth and rebirth.
Most European celebrations of the winter solstice involved merriment and feasting. In pre-Christian Scandinavia, the Feast of Juul, or Yule, lasted for 12 days celebrating the rebirth of the sun god and giving rise to the custom of burning a Yule log.
In ancient Rome, the winter solstice was celebrated at the Feast of Saturnalia, to honour Saturn, the god of agricultural bounty. Lasting about a week, Saturnalia was characterised by feasting, debauchery and gift-giving. With Emperor Constantine’s conversion to Christianity, many of these customs were later absorbed into Christmas celebrations.
One of the most famous celebrations of the winter solstice in the world today takes place in the ancient ruins of Stonehenge, where thousands of druids and pagans gather to chant, dance and sing while waiting to see the spectacular sunrise.
To calculate the turning point in your time zone, click here.