Egypt is preparing to use the latest technology to solve a 4,500-year-old riddle.
A robot is to be sent up two narrow shafts in the Great Pyramid in Giza to discover whether a secret burial chamber contains the real tomb of the pharoah Cheops, also known as Khufu.
The chief Egyptian archeologist, Zahi Hawass, is to inspect the robot designed by Singapore scientists later this week.
He was the official who breathlessly watched with a live television crew and a group of the world's leading egyptologists in September 2002, when an American-designed robot drilled a hole through a stone panel in a pyramid shaft.
In an historic anti-climax, after crawling 200 feet along caterpillar tracks, the robot revealed nothing but another sealed door at the end of a small empty chamber.
The Singapore team has been working on a new robot for the last two years.
The device is to drill through the second door and a stone slab blocking the second shaft in the pyramid which is the largest in the world and stands at the gateway to Cairo.
"It's very important to reveal the mystery of the pyramid.
Science in archaeology is very important.
People all over the world are waiting to solve this mystery," Dr Hawass told Reuters.
"I believe that these doors are hiding something...
It could be, and this is a theory, that maybe Khufu's chamber is still hidden in the pyramid," he said.
The two shafts, which rise from an unfinished chamber in the pyramid and which measure just 8 by 8 inches, have puzzled archaeologists since they were first discovered in 1872.
They are peculiar to the Cheops pyramid - none have been found in any other.
It was initially thought they were air vents, but experts say it is more likely that they were built as a ritual passageway for the dead pharaoh's soul to reach the afterlife.
The pyramid, which was plundered by tomb robbers thousands of years ago, was built by King Cheops in 2,500 BC.
If the new probe uncovers the secret burial chamber, it could mean that none of the chambers discovered so far were the pharoah's actual tomb.
The King's Chamber leads to a room almost exactly at the centre which holds the pharaoh's red granite coffin.
The Queen's Chamber is believed to have held a statue of Khufu, but has never been used.
The pharoah's wives are buried in smaller pyramids nearby.
The first probe through the shafts was sent by a German team in 1993, but the robot was blocked by the limestone panel.
Rudolf Gantenbrink, the German team leader, says on his website that when it is known what lies behind the slab "we will almost certainly learn why those two lower shafts were specially constructed to be totally invisible.
And we will finally gain the long-sought key we require to unlock the overall mystery of the Cheops Pyramid." Dr Hawass said he hopes that "in a few months from now we will really know what's behind them."