Somehow, while the rest of the ancient Egyptian world has crumbled around it, the Great Pyramid of Khufu at Giza remains standing, even after 4,600 years.

Hard limestone rock used to build the pyramid is reducing its risk of damage, scientists suspect

Somehow, while the rest of the ancient Egyptian world has crumbled around it, the Great Pyramid of Khufu at Giza remains standing, even after 4,600 years.