There were pyramids built in ancient Egypt.

And the ancient Mayans also built pyramids.

There are those who believe that this proves they both got the idea
from the civilization of ancient Atlantis. Or Lemuria. Or from
brothers of men who piloted flying saucers.

Of course, as we know, the explanation is far more prosaic. Back in
the days of ancient civilizations, they didn't have steel girders or
even rebar, metal being scarce and expensive, and thus wood was the
only construction material they had with appreciable tensile strength.

So, instead, they built permanent structures of rock, which has
compression strength only - leading to pyramids being the obvious
choice if a really large and imposing structure was desired.

Of course, there was influence from Egypt on the pyramids of Sudan.

This lealds to an obvious conclusion, which could even be the premise
for a science-fiction story of sorts.

As humanity explores space, and eventually encounters alien life...
alien intelilgent beings, early in their history, at the dawn of their
civilizatiions... may *also* have built pyramids of their own.

And it may be that even when humanity has mastered the secret of
faster-than-light interstellar travel, there will still be those who
are unintelligent and ignorant and thus unready to face this
revelation... and will be convinced that, if there are pyramids on an
alien world, they must have had a common origin with the pyramids on
Earth!

John Savard