Pest is the eastern, mostly flat part of Budapest, Hungary, comprising about two thirds of the city's territory. It is separated from Buda and Óbuda, the western parts of Budapest, by the Danube River. Among its most notable sights are the Inner City, the Hungarian Parliament Building, Heroes' Square and Andrássy Avenue. In colloquial Hungarian, "Pest" is often used for the whole capital of Budapest. The three parts of Budapest united in 1873.