YouTube star spent years digging a secret underground tunnel between his house and his workshop before he applied for planning permission.Colin Furze said despite one authority expressing fears of subsidence, it was easier to get permission for the large tunnel after the majority of it had already been built. The Lincolnshire star has been documenting the project on his YouTube channel, which has nearly 12 million subscribers, and focuses on his big projects and wacky inventions, which have included everything from a hot tub BWW to a triple bath and slide.Starting in 2018, this is one of the 42-year-old's biggest projects, and has seen the construction of a 1.2 metre wide by two metre high tunnel to link the workshop at his Stamford home to his house.