Romans. Hands down.
I look at the pyramids and no matter how awe-inspiring they are, they are useless. It serves almost no pratical purpose. I don't like this.
The romans got engineering right.
Take the Pont Du Gard, for example. It's definitely not as impressive as the pyramids. But it is an superb building that impressed and impressed people across time. And what it was? A aqueduct and a bridge. Simple. Yet grand.
So, let me post my top5 roman buildings:
1) The Pantheon. I was watching a Yale curse about roman architecture and the teacher there said she thinks this is the greatest building ever built. Like, ever. By anyone. And I might agree. Certainly in the top10. Notice the size of the people inside it. That dome is HUGE. More than 40 meters both in diameter and in height (it's actually the same, so you could fit a perfect sphere inside the temple). Also, it's made of concrete, and the composition of the concrete changes, so it gets lighter. The Pantheon is not only pretty to look at. It shows roman abilities with building materials (concrete, in particular) and great knowledge of structural engineering.
2) Colosseum. The best known roman bulding. A engineering marvel by any standard. I always remember a scene from Gladiator when they first see this building. And the Nubian is like "I didn't know men could built such a thing". And this always make me wonder how people reacted the first time they saw, not only the colosseum, but any of the grandest roman constructions.
3) Alcántara Bridge. It's not just the bridge in itself, but the whole idea of bridge building in acient Rome. So many rivers were crossed in so many places like never before. I wish I could see Trajan's Bridge, and especially Caesar's military bridges.
4) Via Appea. Again, it's not the building itself, but the whole concept it represents. Any nation is those times could build roads, but like the romans? Paved, straight, drained? And in that scale? I don't think so.
5) Pont Du Gard. I'm tired of writing. Let someone else do the talking for me: "I had been told to go and see the Pont du Gard; I did not fail to do so. It was the first work of the Romans that I had seen. I expected to see a monument worthy of the hands which had constructed it. This time the object surpassed my expectation, for the only time in my life. Only the Romans could have produced such an effect. The sight of this simple and noble work struck me all the more since it is in the middle of a wilderness where silence and solitude render the object more striking and the admiration more lively; for this so-called bridge was only an aqueduct. One asks oneself what force has transported these enormous stones so far from any quarry, and what brought together the arms of so many thousands of men in a place where none of them live. I wandered about the three storeys of this superb edifice although my respect for it almost kept me from daring to trample it underfoot. The echo of my footsteps under these immense vaults made me imagine that I heard the strong voices of those who had built them. I felt myself lost like an insect in that immensity. While making myself small, I felt an indefinable something that raised up my soul, and I said to myself with a sigh, "Why was I not born a Roman!" - Jean-Jacques Rousseau
That's it. I really hope I can see them all in person one day.