Tiananmen Square is the third largest public square in the world, covering 100 acres. It was used as a public gathering place during both the Ming and Qing dynasties. The square is the political heart of modern China. Beijing university students came here to protest Japanese demands on China in 1919, and it was from the rostrum of the Gate of Heavenly Peace that Chairman Mao announced the establishment of the People's Republic of China in 1949. More than a million people gathered here in 1976 to mourn the passing of Communist leader Zhou Enlai. In 1989, the square was the site of massive anti-government student demonstrations.