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In Geneva, there is a United Nations building - and if you step inside you've left Switzerland.
I've also visited and taken a tour of the UN building in New York - it's well worth braving the security line to get in. You get to see the Security Council chamber and the General Assembly, which is much larger that it appears on the TV.
Now okay, the UN might not issue currency - but they do issue stamps (and the New York building even has its own post office) and other countries send Ambassadors to the UN, so in my book the United Nations is a "country" - (and I've already got a "U" anyway!!)
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