New Pathways
If you cannot get from one place to another, maybe you need a bridge, tunnel, or road. A person trained as a special kind of engineer can help you. Civil engineers design and construct highways, harbors, bridges, and tunnels. These engineers have specialized training in physics and math. Frequently, they are also talented architects.
Most people think of bridges as structures that cross waterways, but bridges have been built to go across other wide spaces as well. Centuries ago, bridges were usually made of wood and rope. They were built to help people cross deep canyons between mountains. Now bridges are often constructed in large cities. They allow people to cross between buildings and tall skyscrapers.
Engineers build bridges primarily for cars, trucks, and trains. Sometimes several levels are built, one for cars and trucks and one for trains. Cars and trucks may be routed through different levels, but what about people? They deserve a pathway across a bridge, too. People like to stroll, ride bikes, and even jog across bridges. Many bridges now have designated pathways just for people without automobiles.
Civil engineers also build tunnels. Recently, a tunnel that connects England and France was built beneath the English Channel. For the first time in history, people can drive their automobiles from the United Kingdom to the mainland of Europe.
What are bridges used for?
Why do bridges need special pathways?
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