Istanbul is the only city which has parts in two continents, Asia and Europe.

And as you know most of the world countries are suffering of economic crysis. While some Western countries deals with this economic crisis, Middle-Eastern people are dealing with their former and current regime of their governments. But when world deals with these problems, Turkey and Istanbul stands as the center of the world with   it's position (geographically and politically), which makes Turkey able to impersonates as mediator and negotiator to solve all problems of the world, both Eestern countries' and Eastern countries' .

Meaning of Olympic Rings :

"The five interlocking rings represent the five continents brought together by the Olympic Movement, or the five main regions: Africa, the Americas (North and South America are combined), Asia, Europe and Oceania. As it says in the Olympic Charter, the five-ringed symbol "represents the union of the five continents and the meeting of athletes from throughout the world at the Olympic Games." The symbol of the Olympic Games is composed of five interlocking rings, colored blue, yellow, black, green, and red on a white field. The colors of the rings represent the flags of the countries that participate in the Olympics. Every flag of a country participating in the Olympics includes one of those colors. "

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International Olympic Committee's (IOC) mission and role :

The stated mission of the IOC is to promote Olympism throughout the world (1) and to lead the Olympic Movement.

The IOC's role is to:

1 - Encourage and support the promotion of ethics and good governance in sport as well as education of youth through sport and to dedicate its efforts to ensuring that, in sport, the spirit of fair play prevails and violence is banned

2 - Encourage and support the organization, development and coordination of sport and sports competitions

3 - Ensure the regular celebration of the Olympic Games

4 - Cooperate with the competent public or private organizations and authorities in the endeavor to place sport at the service of humanity and thereby to promote peace

5 - Take action in order to strengthen the unity, to protect the independence of the Olympic Movement, and to preserve the autonomy of sport;

6 - Act against any form of discrimination affecting the Olympic Movement

7 - Encourage and support the promotion of women in sport at all levels and in all structures with a view to implementing the principle of equality of men and women

8 - Lead the fight against doping in sporting

9 - Encourage and support measures protecting the health of athletes

10 - Oppose any political or commercial abuse of sport and athletes

11 - Encourage and support the efforts of sports organizations and public authorities to provide for the social and professional future of athletes

12 - Encourage and support the development of sport for all

13 - Encourage and support a responsible concern for environmental issues, to promote sustainable development in sport and to require that the Olympic Games are held accordingly

14 - Promote a positive legacy from the Olympic Games to the host cities and host countries

15 - Encourage and support initiatives blending sport with culture and education (2)

16 - Encourage and support the activities of the International Olympic Academy(IOA) and other institutions which dedicate themselves to Olympic education

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(1) : It indicates that every part of the world should be able to host Olympic Games, if you look at other candidate cities, Madrid and Tokyo, you can see that unfortunately Spain is under pressure of the economic crisis, that is why it may cause problems when planing and hosting the Olympic Games. If you look at Tokyo, you can see that Japan have hosted five Olympic Games which two of them hosted in Tokyo when Turkey haven't hosted any yet. If Olympic Games are international , now it's Turkey's turn. (List of Olympic Games host cities - Click)

(2) : If culture is a very important piece of Olympic Games, without a doubt Turkey and especially Istanbul has an advantage with it's unique history and geopolitical position. 

Napoleon Bonaparte : "If the whole world was a state, Istanbul would be the capital of it."

Alphonse de Lamartine : "If one had but a single glance to give the world, one should gaze on Istanbul."

And many more...

More information on Istanbul :

Wikipedia - Click

Wikitravel - Click

Istanbul Metropolitan Municipality - Click