Defining Plaza de Mayo’s northwest edge is Palacio de Gobierno Ciudad de Buenos Aires (Buenos Aires City Hall). Soon after it was finished in 1893, the space was deemed inadequate so an annex was added in 1914. Mayors ran the city here from 1883 until 1996. After an amendment by the Argentine Constitution allowed for more self-governance, the mayor title was changed to the Chief of Government. The chief and vice-chief office in the Buenos Aires City Hall.