Windows on the World closed after the 1993 bombing , in which employee Wilfredo Mercado was killed while checking in deliveries in the building 's underground garage . It underwent a US$ 25 million renovation and reopened in 1996 . In 2000 , its final full year of operation , it reported revenues of US$ 37 million , making it the highest-grossing restaurant in the United States
1993 bombing
1993 World Trade Center bombing
Windows on the World