What is "treriksroeysa"

Treriksrøysa ( Norwegian: Three-country border cairn). Norway has two three-country land borderpoints and also two cairns of a similar type. The western is on the meetingpoint of her borders to Finland and Sweden, and the eastern on the meetingpoint of her borders to Finland and Russia. The western one is located only north of the eastern one, even if they are more than apart.