Eric Hines, age 11, of Louisville, Ky., for his question:
HOW WERE THE EGYPTIAN PYRAMIDS BUILT?
Ruins of 35 pyramids still stand in Egypt near the Nile River. Each one was built to protect the body of an Egyptian king. Ancient Egyptians believed that a man's body had to be preserved and protected so that his soul could live forever. The body of each king was ipummified, which means that it was dried and wrapped, and then it was placed. in a pyramid's secret tomb.
Most of Egypt's famous pyramids were built about 4,500 years ago as burial tombs for Egyptian rulers. They had square bases and four smooth, triangular‑shaped sides that came to points at the top.
Just outside present‑day Cairo, you can find the three largest and best preserved of all the Egyptian pyramids. One of them, built for King Khufu, is called the Great Pyramid. A marvel of building skill, the gigantic structure's base covers an area large enough to hold 10 football fields.
The Great Pyramid is made up of more than 2 million stone blocks that average about two and a half tons each. The pyramid was originally 481 feet tall, but some of its upper stones are gone and today it stands 450 feet high. The base covers about 13 acres.
It wasn't easy to build the Great Pyramid and the other structures. The ancient Egyptians didn't have machinery or iron tools. All of the big limestone blocks had to be cut with copper chisels and saws.
Most of the stones came from nearby quarries, but some of the giant blocks came from across the Nile River and others arrived by boat from distant quarries.
Large teams of men had to drag the blocks to the pyramid ' site and push the first layer of stones into place. They then built long ramps of earth and brick, and dragged the stones up the ramps to form the next layer.
As they finished each layer, the workers raised and lengthened the ramps. Finally, after the topmost stone was in place, they covered the pyramid with an outer coating of white casing stones.
Rocks were hauled on sledges. Timbers were laid on the ramps to reduce the friction of the sledges, and then long levers were used to ease the blocks around corners.
It has been estimated that 400,000 men worked each year for 20 years to build the Great Pyramid.
While archaeologists don't know exactly how many men were employed and how long it took to build each pyramid, they know each project was a great accomplishment.
The burial chamber inside the Great Pyramid is considered to be one of the marvels of ancient architecture. It is at the end of a 153‑foot‑long corridor that is 28 feet high.