That's the $10,000 question.
Plus a buried pyramid in Scotland. There are hills in China that when seen from the air are square as if they hid them under dirt - but people, especially foreigners, are forbidden to go there. Try Angkor Wat in Cambodia. Egypt. Mexico. South America. Pumapunku in Bolivia. All cultures that would have no way to communicate, or travel, with each other have distinct similarities. Some uncovered ruins in Sumeria about 10,000 years old that have tablets of our solar system, including all proportionately sized planets in correct orbits. Even Pluto - that we didn't discover until about 1930.
Look at the Giza Plateau, the pyramids are not quite in a straight line - a little bent, when the building and orientations are so exacting. It matches the same exactly with the layout of Teotihuacan in Mexico - a little bent, exactly the same way.
Try watching "Ancient Aliens". I think you can google it for reruns. Really fascinating stuff. Good scenery. But I would not put too much stock in their conclusions - they have been debunked a lot for over reaching, and some lies. Still interesting to see - draw your own conclusions.