The WTC in New Generation City has 3 skyscrapers, a fountain, a statue of a pikachu and a Unovan Flag.
The Skyscrapers (1 WTC, 2 WTC and Offices of the South) are all office buildings, they are triplet towers.
10 years after people: Not much has changed other than the fountain stopped and the offices are moldy.
100 years after people: The flag blows away, and the statue and fountain begin to fall into vegetation.
150 years after people: The statue collapses, the flagpole tips over and the fountain leans. The towers remain.
250 years after people: Offices of the South's steel frame crashes into 2 WTC which crashes into 1 WTC.