Macchu Pichu is an earthquake-proof city

This ancient Inca town rests on top of two fault lines in Peru. That means earthquakes were expected events. So how did they live through it?

In fact, the Incans created a brilliant engineering technique called ‘ashlar masonry’, where rocks are cut to fit perfectly together without mortar. This allowed the stones to move in its place during an earthquake, before settling back in their original positions.