Well, there were the Egyptian Pyramids, Great Wall of China, Roman Aqueducts and a whole bunch of Great Projects in the past and I certainly hope there will be lots more in our future.
As far as I know, the pyramids were each constructed for a single pharaoh, and during their single lifetime. I don't know about all of them, but that's at least true of Great Pyramid of Giza.
Or just a few turns, depending on your difficulty setting. (-;
We don't know how some of the Egyptian pyramids were constructed, or when, or how long it took.