They are considered one of the wonders of the world and have left archaeologists wondering how they were built in the middle of nowhere more than 4,000 years ago. We are talking about the pyramids of Egypt
Now scientists believe they may have solved the mystery of how 31 pyramids, including the world-famous Giza complex, were built in Egypt more than 4,000 years ago.
According to researchers at the University of North Carolina, Wilmington, the pyramids were built with the help of a branch of the Nile River, which is hidden under desert and farmland.

For many years, archaeologists had suspected that the ancient Egyptians must have used a nearby waterway to transport materials such as stone blocks to build the pyramids.
But until now, no one was sure about the location, shape and size of this waterway.
The team of researchers used satellite images, historical maps and geophysical studies to map the branch of the river that they believe was dried up by a severe drought thousands of years ago.
The team finds that the branch was approximately 64 km long and between 200-700 km wide. The river branch was bordered by 31 pyramids, which were built between 4700 and 3700 years ago.