In pictures: The world goes blue for Royal baby boy

epa03797952 A message is displayed on a large screen at Melbourne's Federation Square offering congratulations on the arrival of Britain's Prince William and Princess Kate's baby boy, in Melbourne, Australia, 23 July 2013. EPA/HAMISH BLAIR AUSTRALIA AND NEW ZEALAND OUT *** Local Caption *** 03797952.jpg

To celebrate the birth of a baby boy to Britain's Prince William and wife Catherine, the Duke and Duchess of Cambridge, the CN Tower is illuminated in blue light, in Toronto. Warren Toda / EPA

Blue lights illuminate the Golden Jubilee Bridges over the River Thames in central London. Will Oliver / AFP

Visitors to Niagara Falls receive notice of the sex of the royal baby indicated by the blue light illuminating the falls in Niagara Falls, New York. John Normile / Getty Images / AFP

Christchurch Airport will be lit blue each night for the next week to welcome and celebrate the arrival of the future king. New Zealand is sending the baby a shawl made from fine New Zealand wool, while a 21-gun salute will take place in the capital Welli???

Lightning strikes behind The London Eye in central London which is lighted up in the national colors of red, white and blue to mark the birth of Prince William and his wife Kate's first child Tuesday. Lewis Whyld / AP Photo

The Peace Tower on Parliament Hill is lit blue to celebrate the birth of a baby boy to Britain's Prince William and Catherine, Duchess of Cambridge, in Ottawa. Chris Wattie / Reuters

The British Telecom tower displays "it's a boy" to mark the birth of a baby boy for Catherine, Duchess of Cambridge and her husband Prince William. Paul Hackett / Reuters

The fountains in Trafalgar Square are illuminated in blue to mark the birth. Bogdan Maran / EPA

A staff member, centre, of the Madame Tussauds Tokyo wax museum prepares decorations next to the wax figures of Britain's Prince William and his wife Catherine, before it's opening hours in Tokyo. Issei Kato / Reuters