The Whitney Block is an important provincial office building located in Toronto, Ontario. It is located across the street from the Ontario Legislature, and contains the offices of the Premier of Ontario and most cabinet ministers. The street address of Whitney Block is 99 Wellesley Street West, though the principal facade faces west towards Queen's Park Crescent and the Ontario Legislature. The building is linked to the legislature by a tunnel under the street, by a bridge to the Macdonald Block, and through there via another tunnel to the subway. The Modern Gothic-Art Deco structure was built in 1926 by architect F. R. Heakes and the tower was added in 1932. Whitney Block is faced with Queenston limestone.