This is what I was thinking too. The only projects I could figure that have lasted that scale of length are things like cathedrals, the pyramids of Giza, the Gr

This is what I was thinking too. The only projects I could figure that have lasted that scale of length are things like cathedrals, the pyramids of Giza, the Great Wall of China, etc. All of these are attached to religion, or at least a supernatural belief in the person driving it.