The Assyrian homeland, Assyria, refers to the homeland of the Assyrian people within which Assyrian civilisation developed, located in their indigenous Upper Mesopotamia. The territory that forms the Assyrian homeland is, similarly to the rest of Mesopotamia, currently divided between present-day Iraq, Turkey, Iran and Syria. In Iran, the Urmia Plain forms a thin margin of the ancestral Assyrian homeland in the north-west, and the only section of the Assyrian homeland beyond the Mesopotamian region. The majority of Assyrians in Iran currently reside in the capital city, Tehran.