EGYPT: There are few monuments as compelling as the Great Pyramid at Giza. Adventurers, explorers and archaeologists have been trying to penetrate its secrets for thousands of years.
This morning, a team of archaeologists, led by Dr Zahi Hawass, director of Egypt's Supreme Council for Antiquities, attempts to solve one of the last remaining mysteries of this most enigmatic of structures.
The operation will be broadcast live to millions of viewers around the world by the National Geographic Society, the expedition sponsors.
Using a small robot similar to ones used to find survivors of last year's attacks in New York, the archaeologists will attempt to discover what is at the end of a long shaft deep inside the pyramid's core.
There are a number of shafts inside the mass of the Great Pyramid, and most of them bring fresh air into the burial chamber.
The dimensions of the shaft in question - 20cm by 20cm - prevented archaeologists from exploring it until 1993, when a German team of academics sent up a robotic camera with a laser-measuring device. The robot was forced to stop when it encountered a limestone door with two copper handles, prompting speculation about what could lie beyond.
It was to answer this riddle that the new robot was designed. Measuring only 12cm wide and 30cm long, it can not only take pictures inside the shaft but is equipped with a drill which can send a fibre-optic cable through the rock and transmit pictures of what lies beyond.
As the pyramid was robbed in antiquity, the treasure which would have accompanied a royal burial was never found. Few expect such a trove to be found behind the limestone door.