The United Nations Tower is a cancelled observation tower in San Francisco.But if it were built,how long would it last in a life after people?
50 years after people: The glass in the metal frame around the steel pillar holding up the globe-like observation pod finally shatters onto the Alcatraz Island on which it sits.
200 years after people: The steel pillar is starting to weaken. The steel frame is also under pressure by the observation pod. Finally, the pod punches through the pillar. The rubble pushes out the steel frame. Much of it damages the Alcatraz prison, then falls into the water.