Although some races are unsanctioned, held under the sole guidance of a local club, many races fall under one of three international organizations. In the United States and Canada, ISDRA (International Sled Dog Racing Association) sanctions many races. In Europe, ESDRA (European Sled Dog Racing Association) provides sanctioning, and the IFSS (International Federation of Sleddog Sports) sanctions World Cup races all over the world, as well as a world championship race every two years. At the IFSS World championship event, skijoring races are separated into men's and women's, and one-dog and two-dog categories. The USA held the world's largest skijoring event in February 2011 at the City of Lakes Loppet in Minneapolis. Two hundred skijoring teams raced in this event, which included the first-ever National Skijoring Championship.