A tunnel is a long hole that is dug underground. Many animals make tunnels and so do people. Tunnels are made and used for many things.
Animals make and use tunnels. Ants, worms and snakes make little tunnels to live in. They push and move dirt to make their way. Moles, chipmunks, prairie dogs, and rabbits make tunnels. These animals use their front paws or feet to dig their tunnels.
People make tunnels, too. You can make a tunnel in the dirt by digging with a small shovel. Tunnels can be made by digging from one end and then digging from the other end to meet in the middle.
Tunnels are used by people, too. They can be made through rock. Rock tunnels top and bottom are strong because the rock is hard. People build tunnels to go through mountains.
Another kind is the soft ground tunnel. It is made by digging through clay, sand, or wet ground. It will need to have support on all sides, top and bottom. Construction workers use metal to make it sturdy, so it will not fall in.
Some tunnels are made by first building the walls and bottom, then putting dirt over the passageway.
Tunnels take a long time to build. There are different uses for tunnels. Tunnels can be used to carry water from one place to another in water plants. Gas pipelines are also tunnels to carry gas from one area to another. Miners use tunnels to get out coal and other minerals. You can find tunnels in some cities, too. Tunnels are found in subways, and underground walkways. They go under streets, through mountains, and through waterways.
Tunnels are made and used by animals and people for many important reasons.