The Great Pyramid

The precision of this structure is rarely matched to today and in fact wasn't matched until the 1800s. The actual foundational work that went into the ground to prepare and build on top of is just as interesting like an engineering challenge and puzzle because they must have spent years and years preparing the site. They created a foundation layer for the pyramids and in particular on the middle pyramid it's actually built into this sliding like a sloped hill which integrates sloped with the slope of the hill into the rest of the structure.