Picture yourself standing on one side of a raging river that’s filled with hungry crocodiles. You really want to get across the river, but swimming with crocodiles is out of the question, and walking around the river could take several days.
What should you do? Aha! Build a bridge!
From the earliest footbridges, built with a single fallen tree trunk or flat stones, to structures made with spun steel cables, bridges have played key roles in our world. They have gotten us “to the other side” and they have protected us from enemies. They have also increased trade and long-distance travel. Bridges combine beauty with usefulness. But why are some curved and others straight? Why are some made of stone, others of wood, and yet others of steel and aluminum? Read on to find out.