Deep in the Norwegian forest there is a tree forever destined for London. Every year Olso gives us a Christmas present of a spruce - an annual thank you present for support during World War Two. This year we'll receive tree number sixty-six.
But it takes years of meticulous planning to select the right one. Out of the millions of spruces, only one will be selected to make the annual trip. Jon Christiansen is head forester at Oslo City Council. Like a real life Santa his job is dedicated to make sure we get the best at Christmas.
Christiansen singles out the best trees years in advance. He already has his eye on the spruce he will send to London in ten years' time.
"A good tree has branches all the way down", he says. "If we spot a good one and it continues to grow well, we will cut down the trees around it so it gets enough light."
You know Christmas is here when Trafalgar Square gets its tree. Picked in the wilderness, the spruce ends up in the heart of our city.
From a tradition that has its roots in the darkness of war, it continues to give light to Christmas.
The Lord Mayor of Westminster, Angela Harvey, has travelled to Norway to oversee the cutting of the Trafalgar Square Christmas tree. Describing the annual felling as "a wonderful tradition", she said that for her it wasn't Christmas until the Trafalgar Square tree was lit.
The Mayor of Oslo, Fabian Stang, has overseen the annual felling of a Norway spruce tree for Trafalgar Square. The tree is typically a 50- to 60-year-old tree, over 20 metres tall.
After the tree is cut, it is shipped to London by sea.
At the base of the tree stands a plaque, bearing the words:
This tree is given by the city of Oslo as a token of Norwegian gratitude to the people of London for their assistance during the years 1940-45. A tree has been given annually since 1947.