A couple hiking up a Swedish mountain stumbled upon a footwear collection with a difference – 70 pairs of shoes filled with butter.

The stunned pair were climbing a mountain in the country's far north when they discovered 140 trainers, high heels and boots scattered in the snow and filled with butter.

Puzzled environmental officials, who believe hikers may have copied a display called "Shoes with Butter" designed by artist Yu Xiuzhen in 1996, plan to remove the collection when the snow melts.