Oldham hosts Europe's only dedicated roller derby centre
Although roller derby started in the United States, there are more than 100 leagues in the UK.
The North West is thought to have the only dedicated facility in Europe, the Thunderdome in Oldham.
Now as part of BBC Sport's Get Inspired campaign, several teams, including Oldham's Rainy City Roller Girls, feature in a new film about the sport.
Naomi Cornwell reports.