What began as a small, informal 5K run with just 13 participants in a London park in 2004 has grown into a global movement, with more than 10 million people having participated. On a crisp autumn morning in 2004, 13 runners gathered in London's Bushy Park for an informal 5 kilometre run, unknowingly setting the stage for what would grow into a global fitness phenomenon. “I didn’t know who was going to join me on that day,” says Paul Sinton-Hewitt, the founder of (yes, it's all lowercase).

“I didn’t care how many people came. I would be on the start line every single week for the rest of my life and I would help people to run.” What began as a local, weekly gathering soon transformed into something far beyond what Sinton-Hewitt, a software developer who grew up in South Africa, had ever imagined.

Two decades later, parkrun celebrates its 20th anniversary, with over 2,500 events taking place across more than 20 countries, including in 25 prisons. With more than 10 million participants and over 100 million recorded finishes, parkrun has become a worldwide movement. For the uninitiated, parkrun is an organised weekly 5-kilometre (3.

1 mile) fun run, held in local parks around the world. It was started by Sinton-Hewitt with the goal of providing an accessible, inclusive, and non-competitive running event for people of all ages and abilities. The volunteer-run meetups are open to anyone and everyone, and even better, are completely free! Attendees are encourage to walk, .