Officially the Avenue of the Americas since 1945, yet still called Sixth Avenue.
Sixth Avenue was laid out in the Commissioners' Plan of 1811. In 1945 the City Council renamed it Avenue of the Americas at the request of Mayor Fiorello La Guardia, who signed the bill on 2 October, to honour Pan-American ideals and the nations of Central and South America. New Yorkers largely ignored the change: a 1955 informal study found 'Sixth Avenue' used more than eight times as often.