Starting Aug. 15 in Duluth, Minn., the top 60 leagues in the Women's Flat Track Derby Association will compete in a six-game tournament series leading up to the Championships to be held in Nashville, Tennessee.

From Duluth, the action will move to Kitchener-Waterloo in Ontario, Canada, to determine which Division 2 teams will advance to the Championships.

The 40 Division 1 teams will compete in the remaining four tournaments for the chance to play in Nashville in the championship tournament to be held from October 31 to November 2.

Event information and tickets are available online and those unable to attend the tournaments can watch them on WFTDA's broadcast channel.

Later, top athletes from 30 countries around the world will face off in Dallas for the Blood & Thunder World Cup, scheduled to take place from December 4-7. Tickets are available now.

To qualify, athletes must try out for their respective country's team.

Roller derby is a contact sport performed on classic roller skates (not roller blades, or inline skates) on a flat track much like those for running that is often banked.

Two teams consisting of five players each race around the track in the same direction, each team working together to send their scoring player, called "the jammer," past members of the opposing team in the aim of scoring points.

The women's version of the sport, which can be traced to 1930s Chicago, has exploded in popularity all over the world.

When the WFTDA was formed 10 years ago, it had less than 30 teams on its roster. It now has 259 member leagues and 98 apprentice leagues.

South America, Europe, Australia, New Zealand and Japan have all joined in on the action and have established leagues. The website counts 1,515 teams worldwide as far as Malaysia.