…About 200 hundred years ago, a man named Darby built the first iron bridge. It crossed the River Severn in England. It was very strong and cars and trucks still use it today. Bridge builders then began to use iron and steel to make two kinds of bridges. The first kind is the suspension bridge. “Suspension” means “hanging.” There are usually two or more towers which hold up very strong cables. The ends of the cables are fastened at each side of the river. The bridge hangs down from the cables. The longest and most famous suspension bridge is the Golden Gate Bridge in San Francisco in the U.S. The other kind of steel bridge doesn’t have cables. It is made in a number of different parts. Each ready-made part is very strong and joins on to the next part....
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