After a year of preparation, a team of scientists, archeologists and researchers tried early Tuesday to learn a 4,500-year-old Egyptian secret. But the secret still remains.
The team was trying to solve one of the world's greatest mysteries. How Egypt's largest pyramid was built.
The researchers gathered in the early morning hours Tuesday inside the 4,500-year-old pyramid of Cheops, located just outside of Cairo. With them was a toy train-sized robot fitted with a light, a drill and a tiny camera.
The robot, which archeologists dubbed the Pyramid Rover, crawled for two hours in a narrow 60-meter-long shaft in the pyramid, drilled a hole through a door, pushed the camera inside - and found another sealed door made of stone, which prevented the robot from going any further.
The researchers were hoping that by gathering information about the shaft, the robot would provide them with clues as to how the huge pyramid was constructed. But even though they did not get all the answers they wanted, the scientists say they are pleased with what they learned Tuesday.
"Just discovering the first door was a significant find," said Zahi Hawass, director of Egypt's Supreme Council of Antiquities, which sponsored the event. "To find space in the pyramid is something important. Now you find next door to this door another sealed door and it looks like it's hiding something. So, the mystery will continue and the research will continue."
An engineering firm in Boston, Massachusetts, built the robot, and much of the project research was done by scientists at the National Geographic magazine. The robot's travels inside the pyramid were broadcast live on National Geographic television.
The pyramid, which stands 146 meters tall, is made of more than two million stone blocks and contains four narrow shafts. For more than a century archeologists have been wondering why such shafts were built and what secrets they might hold. Scientists theorize the shafts may have been built to serve the departing soul.
Researchers say the next job will be to analyze the footage and plan for further inspections, which could take up to a year.