You might not know it, but John Hancock Center is one of only 32 towers WORLDWIDE with membership to this exclusive club.
Not that you can just 'join' of course - you have to be invited based on a set criteria. Apart from taking the shape of a tower (obviously), each structure must represent iconic architectural design, be symbolic of tourism in the city and provide an observation deck for visitors.
For more on the World Federation of Great Towers, visit them online.
LIVE IN THE 606?
Admission is always half off for Chicagoans with 606 zip codes (ID required).