Etruscan Pyramid of Bomarzo, Italy

Historic Mysteries ^ | prior to March 12, 2019 | unattributed

[Fred Nerks]

You're right of course, thanks:

Etruscans dominated from around 700 BCE to 400 BCE. During that time, they built a curious structure out of the volcanic rock in a thickly wooded area of Bomarzo in a nearby valley.

[SunkenCiv]

The Inca used the stones themselves to grind the stones, hence the tight fit. It doesn't seem like an efficient use of labor, though. :^)