After waiting in line for about four and a half hours, the crowd went through a security check. The first group of people to enter Tian'anmen Square started running toward the flag post as fast as they could. Cheng said she and those around her were astonished to see such a scene, which she keeps replaying in her mind.

On Aug 13, she posted footage on the short-video platform Douyin of the people running, which quickly went viral.

One user commented under Cheng's post, which has received more than 455,000 likes, "Maybe the Chinese national team should come to Tian'anmen Square to look for sprinters."

Sprinting to see the flag-raising ceremony in the square has also trended on microblogging site Sina Weibo since Aug 20, with the topic being viewed more than 64.2 million times.

After joining the race to find a good place, Cheng and her friends made it to the front row to watch the ceremony. As the sun started to rise and the sky brightened, the Guard of Honor of the Chinese People's Liberation Army raised the national flag, to the accompaniment of the national anthem.

"From staying up all night waiting with others, to finally seeing the ceremony — the whole experience is special," Cheng said.

It was not the first time that she had seen the ceremony, as she watched it with her parents when she was 4.

"I was too young to understand the significance of the ceremony at that time. Now, I know what it means for people, and why they say watching the ceremony is a must-do event, or even a pilgrimage," Cheng said.