The IBU Summer Biathlon is a sporting event organized by the International Biathlon Union (IBU) which combines trail running or roller skiing and rifle shooting,[1] or sometimes trail running and rifle shooting. It is modeled after the IBU (winter) biathlon, which is an Olympic sport that combines rifle shooting with cross-country skiing. The Summer Biathlon World Championships have been held annually since 1990. Trail running was part of the world championships until 2009.