Had it ever been greenlighted, the Shimizu Mega-City Pyramid would have been 12 times larger than the Great Pyramid at Giza, and capable of housing over 750 thousand people. Proposed as the largest man-made structure on earth, the giant pyramid would have been composed of 55 smaller pyramids, stacked five high.

For better or worse, these buildings were never built. Despite being sentenced to stay on paper, these staggering skyscrapers surely showcase the extent of human ingenuity and dare us to dream just as their architects dared to imagine them.