Okay kiddo, do you know what a bridge is? It's a structure that helps you cross over something, like a river or a valley. A causeway is kind of like a really long bridge, but it's built on land instead of over water.
Imagine you're at the beach and there's this really, really long stretch of sand that goes out to a little island. Normally, you'd have to swim or take a boat to get to the island, but if someone built a causeway, you could just walk or drive right across it.
A causeway can be made of different materials, like concrete, stones or bricks. It's usually made up of lots of tiny sections put together, almost like a puzzle. When all the pieces are in place, it creates a long, straight path that leads you from one place to another.
So in short, a causeway is a land bridge that helps you get from one place to another without having to swim or take a boat!