Okay, kiddo, have you ever played in a fort made out of blankets and pillows before? Well, a tunnel tree is kind of like that, but it's a fort made out of trees instead of blankets and pillows!
People who love nature and want to protect it came up with a cool idea to help protect trees while also creating a fun place to play. They took a tree that was already growing in the forest and carefully cut a hole in the trunk. Then they hollowed out the inside of the tree to make a tunnel.
Inside the tunnel tree, you can crawl through it like a secret hideaway or hide inside the tree to play games with your friends. But there's a really important rule when playing in a tunnel tree: we have to be very gentle and careful so that we don't hurt the tree or any of the other plants or animals living in the forest.
So, the tunnel tree is both fun and helps us learn to appreciate and care for nature. How cool is that?