19 towers visited by Ronald Aptroot
Beurs-World Trade Center
Big Ben
Burj Al Arab
Burj Khalifa
Chrysler Building
Dubai Marina
Eiffel Tower
Empire State Building
Flatiron Building
Freedom Tower
Kuala Lumpur Tower
Montparnasse
One World Trade Center
Petronas Towers
Prague Astronomical Clock
Taipei 101 Observatory
Tower of Pisa
