Seventeen lost pyramids are among the buildings identified in a new satellite survey of Egypt.
More than 1,000 tombs and 3,000 ancient settlements were also revealed by looking at infra-red images which show up underground buildings.
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"To excavate a pyramid is the dream of every archaeologist," says Dr Sarah Parcak.
She has pioneered the work in space archaeology from a Nasa-sponsored laboratory in Birmingham, Alabama and says she was amazed at how much she and her team have found.
"We were very intensely doing this research for over a year. I could see the data as it was emerging, but for me the "A-Ha" moment was when I could step back and look at everything that we'd found and I couldn't believe we could locate so many sites all over Egypt."
The team analysed images from satellites orbiting 700km above the earth, equipped with cameras so powerful they can pin-point objects less than 1m in diameter on the earth's surface.
Infra-red imaging was used to highlight different materials under the surface.