A clock showing a countdown to the start of the London 2012 Olympics is unveiled on March 14, 2011 in London, England. The clock is starting five hours from midnight when 6.6 million tickets for the Olympics will become available and 500 days before the Games start. There is a six-week window to apply for tickets on the London 2012 website.

Partially demolished houses stand in the Vila Autodromo slum with the Rio 2016 Olympic Park in the background in Rio de Janeiro, Brazil, February 25, 2016. (Photo by Ricardo Moraes/Reuters)

Participants run at the “Half-Naked Marathon” at Olympic Forest park in Beijing, China, February 28, 2016. This annual running event which requires participants to run half-naked, was organized to promote environmentally friendly lifestyles. (Photo by Kim Kyung-Hoon/Reuters)

Chase Jackson, of the United States, competes during the women's shot put qualification at the 2024 Summer Olympics, Thursday, August 8, 2024, in Saint-Denis, France. (Photo by Ashley Landis/AP Photo)

A woman tries to eat a water bug at a bar in downtown Tokyo, Japan, February 12, 2017. A Tokyo bar on Sunday offered courageous couples and curious gourmets a special menu of desserts and drinks made with insects ahead of Tuesday's holiday. (Photo by Toru Hanai/Reuters)

A shoebill is displayed at Ueno Zoo in Tokyo August 28, 2012. (Photo by Itsuo Inouye/Associated Press)

A participant in costume uses a mobile phone at a Halloween event in Kawasaki, south of Tokyo, Japan October 29, 2017. (Photo by Kim Kyung-Hoon/Reuters)