If you thought exercise wheels were just for rodents, think again. YouTuber Tom Scott found out firsthand that circular wooden treadmills were actually an integral part of construction back in the day. In the video below, he visits Chateau de Guédelon, a castle in France. As part of a tourist attraction, people are building a medieval castle using materials and methods from the 13th century. The only anachronistic elements are there as safety measures, like a rudimentary braking system on the treadmill crane. “Obviously we’re not trying to discover how many people were killed or injured in the 13th century,” says Sarah Preston, a guide at the castle. So while there’s no modern machinery, there are hard hats, steel-toed shoes, and safety lines.
Scott walks on the wheel, which lifts a load of hundreds of pounds of rocks to the top levels of the castle. He mentions it’s still a workout, though obviously much less effort than lugging heavy rocks up flights of stone steps. Fred Flintstone had the right idea, driving a Brontosaurus crane at his construction site. As Scott says in the video, it does seem more fictional than historical. But the site works with archaeologists, art historians, and experts known as castleologists to ensure accuracy. It will take 35 years to finish the project, much longer than it would have back in medieval times. But this time around there’s designated work hours and they slow down to explain things to tourists.
![Tom Scott walks on a large wooden circular treadmill that powers a crane](https://legendary-digital-network-assets.s3.amazonaws.com/wp-content/uploads/2022/10/20111135/treadmill-crane.jpg)
Other videos on Tom Scott’s YouTube channel include coming face to face with a robot double and discovering the secrets of cinematic explosions. He covers everyday science topics and a collection of “ things you might not know.” As for this video, the only thing left unexplained is, what is a murder hole and why do castles have them?
Melissa is Nerdist’s science & technology staff writer. She also moderates “science of” panels at conventions and co-hosts Star Warsologies, a podcast about science and Star Wars. Follow her on Twitter @melissatruth.