Paris

One of the most prominent symbols of Paris—the Eiffel Tower—was meant to be a temporary installation, but was scheduled for demolition after 20 years.

An excerpt from the article 23 facts about Paris
It was built for the World Fair in 1889. It is 324 meters high, consists of 18,000 metal parts joined together with 2,5 million rivets, and weighs 10,100 tons.