During the world war 2 why were tehran and yalta significant

Tehran, capital of Iran and Yalta located in the Crime are were very significant during World War II, because both locations were used as meeting points of conferences that were made during the war by the big three, where the leaders of the allied powers discussed about how was the war progressing and also discussed the plans after the war would be finished too.  

They were sites of conferences held by the Big Three

Explanation:

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