Despite a popular myth, the Great Wall of China is not the only object made by human beings that can be seen from space. In fact, quite a few manmade objects can be seen from Earth's orbit.

From a height of 135 miles (217 kilometers) above the earth, astronauts in the Space Shuttle can see airports, highways, dams and large vehicles.

Cities can be distinguished from the countryside that surrounds them from 250 miles (400 kilometers) above the Earth, the height of International Space Station's orbit.

Edward Lu, a science officer aboard the ISS, says that you can see the Egyptian pyramids, roads, harbors and large ships.

Several photographs of the Egyptian pyramids have been taken from space, using standard digital cameras with high-powered lenses.

The Great Wall of China is actually more difficult to see from space than many other manmade objects because it is similar in color to the soil that surrounds it.