Comparatively few historical ruins built out of materials that would have lasted this long, but a long history, actually, and some you can still see...

Mexico City is a quick plane ride from the USA, and while some of their ruins are buried, you can hop a short bus ride outside the city to walk among standing ruins of Teotihuacan, the largest city in the Western Hemisphere at the time Jesus walked on the Earth. It was 20 square kilometers whereas Rome at the height of the empire had only 14 square kilometers within the Aurelian Walls.

I've been on the Great Wall of China and all over the world and Teotihuacan was fascinating for me to see. Even more intriguing, no one knows who built it. Aztecs discovered it many centuries after it was abandoned and forever wondered about its origin.