An audio tour is like having a special guide with you when you go to visit a really cool place like a museum or a historical site.
It’s a little gadget that you wear on your ears and it plays a recording of someone’s voice explaining all the things you’re looking at.
The person talking is usually very smart and knows a lot about the place you’re visiting. They’ll tell you all sorts of interesting and fun facts about what you’re seeing.
So instead of just walking around and looking at stuff, you can listen to someone that knows what they’re talking about and learn a lot more!