Chris Warren, age 10, of Tucson, Ariz*, for the question:

How do ancient cities get buried?

We often read that an ancient city has been discovered. And the archeologists always have to dig to find it. There is a good reason for this. People may desert and leave a city, but the weather dons not. The winds bring dust and the rains bring mud. In just a few yours the streets and houses become covered with a fine layer of dirt. New layers get deeper with the passing years and some of those ancient cities have bean deserted. for 1,000 years or more.

Floods and volcanos also help to bury ancient cities. Ancient Babylon was buried under the mud left by a great flood. The city of Pompeii near Naples was buried under the ashes and lava from a volcanic eruption, In desert regions a deserted city is soon buried under the blowing sands. No matter where it may be, a deserted city is soon buried and, centuries later, the archeologists have to dig it up again.