Tehran , Iran.
The official language of Iran is Persian.
Republic Day, 1 April (1979)
note: additional holidays celebrated widely in Iran include Revolution Day, 11 February (1979); Noruz (New Year's Day), 21 March; Constitutional Monarchy Day, 5 August (1925)
Three equal horizontal bands of green (top), white, and red; the national emblem (a stylized representation of the word Allah in the shape of a tulip, a symbol of martyrdom) in red is centred in the white band; ALLAH AKBAR (God is Great) in white Arabic script is repeated 11 times along the bottom edge of the green band and 11 times along the top edge of the red band.