The Great Pyramid of Giza - which is the only remaining structure of the Seven Wonders of the Ancient World - was built around 1,570 BC and the hidden corridor hasn't been seen in 4,500 years ...

The toy train-sized robot is scheduled to crawl 60 metres down a shaft of the Great Pyramid of Cheops, the largest of three pyramids on the Giza plateau near Cairo, on Tuesday.

The largest of the pyramids, the Pyramid of Khufu—also known as the Pyramid of Cheops—was constructed around 4,500 years ago and currently stands at 138.8 meters tall.