Scientists may have solved mystery behindEgypt's pyramids | BBC News

Scientists believe they may have solved the mystery ofhow 31 pyramids, including the world-famous Gizacomplex, were built in Egypt more than 4,000 years ago.

A research team from the University of North CarolinaWilmington has discovered that the pyramids are likelyto have been built along a long-lost, ancient branch ofthe River Nile - which is now hidden.

For many years, archaeologists have thought thatancient Egyptians must have used a nearby waterwayto transport materials such as the stone blocksneeded to build the pyramids on the river.

But up until now, "nobody was certain of the location,the shape, the size or proximity of this mega waterway to the actual pyramids site".