STORY: The 23-day festival, now in its sixth year, features illuminated bridges and buildings with light art scattered around the city.
At the start of the 5 mile (8 kilometre) run, organized by the Danish Architect Center, the runners were given a 13-foot-long (4-metre-long) battery-powered LED light chain to wear during the race, themselves becoming a feature of the festival.
"To be running in Copenhagen with this, with all these artworks and lights all over here in cold February is just fantastic. And I can't wait to see the art," said film director Michael Gug before the race.
Participant Dea Zeeberg said "It was very pretty," while the head of the board of the Copenhagen Light Festival, Jesper Kongshaug, said "There's a lot of love and a lot of people sharing this moment with lights and energy."
During the race, participants passed 21 of the around 55 light installations that can be seen around Copenhagen, mostly concentrated in the city center.