 A founding member of the Women's Flat Track Derby Association (WFTDA), Tucson was the host league for the first WFTDA Championships in 2006.Initially formed as the Tucson extension of the Phoenix-based Arizona Roller Derby, TRD was founded in December 2003 by Kim Kysar (aka Kim Sin) when the Tucson skaters, citing geographical and logistical concerns, broke away from the parent league.By 2006 Tucson Roller Derby was averaging 700-800 fans for home events at Bladeworld, since renamed the Tucson Indoor Sports Center, and still Tucson's home bouting venue as of 2017.