Bridge–tunnel

A bridge-tunnel is like a road that goes underwater like a tunnel and then comes back up above the water like a bridge. It's kind of like a magic trick that lets cars and trucks drive across the water without getting wet.

Imagine taking a really big straw and putting it into a glass of water. Then, imagine putting another glass of water on the other side of the table. Now, if you blew really hard into the straw, the water from one glass could make its way to the other glass.

Now, instead of a straw, we have a really long tunnel that goes under the water. And instead of just two glasses, we have a whole big ocean that we want to cross. So, we build a really long tunnel that goes under the water and comes back up on the other side, like a bridge.

People and cars can then drive through the tunnel and up onto the bridge, and then drive to the other side of the water. It's like a really cool way of getting across the water without having to swim or take a boat.