As exciting as this illustration by Finnian MacManus of Deviant Art is, as a prediction of the future, I have my doubts.
I don’t think we will ever see such massively dense cities in the far flung future, since we already know how damaging to the environment cities are. So why suppose such things should exist? Especially when the fact is that if we carry on as we are doing — over “developing” the planet almost solely to meet human needs to the point of exhaustion — we won’t ever see such a far flung future in the first place.