Arcadia is a suburb in Pretoria, South Africa, that is known for its historical buildings, embassies and hotels. The Union Buildings and the presid…Arcadia is a suburb in Pretoria, South Africa, that is known for its historical buildings, embassies and hotels. The Union Buildings and the president's residence are also situated here. The land on which the suburb lies had the name originally and so it remained after the land was surveyed in 1857/58 by AF du Toit.