這是天安門的禱告聚集在香港的維多利亞公園

_{Editor's note: All links in this article point to Bing results.}

Every year, about 7 million visitors explore Beijing's huge public square, Tiananmen. China has tried to erase the memory of the violent events there in 1989, but eyewitness stories, photos and videos still tell the tale. On the event's 20th anniversary, we take look at what happened that day, June 4, 1989, and since.

Background: Tiananmen Square dates back to the Ming Dynasty when Tianan Gate was originally erected. The square has been the setting for other protests, including this one in 1919 and another in 1976.

What's there? The square is surrounded by a museum, a mausoluem, a hall and the great Tianan Gate (see pictures). In the center of the square sits the giant stone marker. What is it? The square measures around 100 acres, making it the largest open square in the world.

What happened? In April 1989, a former leader of Chinese Communist Party died. Hu Yaobang was forced to resign because of his democratic leanings. On his death, a contingent of students and intellectuals gathered to demand that the party reassess his legacy. That gathering turned into a protest calling for dramatic and democratic reforms. (Search for more about Hu Yaobang's life and how he died.)

The protest: In Beijing, what began as largely a student protest grew to an estimated 1 million Chinese on the streets. (Search for videos.) A statue that largey resembles the Statue of Liberty was erected (search for its name) and several thousand protesters began a second form of civil disobedience, a hunger strike.

China's reaction: Armed troops and tanks entered the square, and shooting began. China said 241 people died. American media said it was as many as 800. Chinese Red Cross said 2,600; Amnesty International 1,000. (Bing finds surviving protesters and their stories.)

"Tank Man": The still unidentified man became a symbol of the clash with his simple act of bravery. Look for pictures and video of him.

"June 4 incident": That's what it's called in China. References to the protest had been removed from literature, and the Chinese government continues to censor Tiananmen Square information. Ahead of the anniversary, it also blocked access to Twitter, Flickr, Hotmail and some blogging Web sites. (Learn more about that story.)