O-Ringen is the world's largest orienteering competition that has continued to grow and innovate for over five decades. O-Ringen takes place in the second half of July and is located in a different part of Sweden each year. In 2020 should the arrangement have been held in Uppsala on 19-25 July.
O-Ringen is a meeting place where 15,000-20,000 orienteers come together for a week each year and who, in total, start roughly 75,000 individual races. O-Ringen attracts competitors from all over the world, and around 40 nations are usually represented.