The Egyptians built the pyramids 5000 years ago. What I find incredible is how we can't seem to build things that last anymore.
Sure, we could build pyramids – better pyramids even than the original ones – but they wouldn’t be terribly useful.
(Oh, and sometimes we do build things that last. The six Apollo descent stages are still on the moon and probably will be for Millennia. That, to me, is a lot more impressive than any pyramid.)
There are innumerable Discovery Channel-esque documentaries explaining that we can barely build a small scale reproduction of the Pyramids, at least using the knowledge they had available then.
https://secure.wikimedia.org/wikipedia/en/wiki/Svalbard_Glob...