The Big O Tournament is an international roller derby tournament hosted Emerald City Roller Derby, a 501c3 organization founded in Lane County in 2007. The tournament includes women’s, men’s, and junior roller derby teams from both the U.S. and around the world, and has grown continually since its inception in 2011.
The tournament is held annually at the Lane Events Center during the first weekend in May. The Big O 2017 will take place from May 5-7.