It’s one of the most basic toys ever invented: a stuffed horse head on a stick. But despite its simplicity, the centuries-old toy has become a catalyst for feminism in Finland.

Hobbyhorse is a new sport taking the Scandinavian nation by storm, born out of a social media subculture among teenage girls, the Associated Press reports.

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And it takes serious athleticism.

Without any official federation, volunteers organize regional competitions throughout Finland. Annual national championships, most recently held last April, feature more than 200 competitors in a variety of events equivalent to actual horse-riding, like show jumping and dressage.

There’s no official count, but approximately 10,000 people, primarily girls between the ages of 10 and 18, are estimated to be involved and it’s spreading to other parts of Scandinavia.

These young Finnish women are starting a Hobbyhorse Revolution — and it's all about empowerment: https://t.co/kNEzTCmX02 via @cbcasithappenspic.twitter.com/03SupcKzzL

— Discovering Finland (@DiscoverFinland) May 8, 2017

The sport doesn’t have strict rules, which fosters creativity and has helped maintain the subculture as a bulwark for girl power.   

“I think hobby-horsing has a feministic agenda,” Alisa Aarniomaki, a 20-year-old former competitor and current organizer, told the AP. “No boys are coming and saying what we need to do, or bossing around. So I think there is some sort of a (feministic) point.”

Beyond allowing girls to set their own rules and expectations, hobby horse has helped some girls through personal struggles.

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Aarniomaki has ridden actual horses since she was 10 years old, but said hobby-horsing has been therapeutic for her, helping her through her parents’ divorce and bullying at school.

“It somehow balances my mind,” she said.

Most of the hobby horses are made by hand with painstaking detail, the AP reports, which proves this is no consumerist toy craze but a cultural phenomenon promoting friendship and camaraderie.

It also brings egalitarianism to riding, a sport which is limited to those who have access to real horses.

“We think it’s simply wonderful that hobby-horsing has become a phenomenon and so popular,” Fred Sundwall, secretary general of the Equestrian Federation of Finland, told the AP. “It gives a chance to those children and teens who don’t own horses to interact with them also outside stables and riding schools.”

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Without any kind of automatic function, the happiness that comes from a hobby horse is completely dependent on the rider – it’s a toy that takes imagination to enjoy.

Through hobby-horsing, thousands of teenage girls in Finland and elsewhere in Europe have an area they can entirely call their own.

And that’s very real.