If you could visit the observation deck of any structure in human history — past, present, or future — which would you choose and what would you hope to see?

The Burj Khalifa's observation deck at 555 meters offers a view of a city that didn't exist 30 years ago. But imagine the view from the Great Pyramid at its completion, or the Eiffel Tower on opening day, or the Jeddah Tower's deck at 500+ meters looking over the Red Sea. Each observation deck is a time machine. The view downward shows what a civilization has built. The view upward shows what it aspires to. Choosing your deck reveals which civilization's dream you want to inhabit.