Her uncle Mei Jingtian, now 80, pioneered the village's Great Wall protection efforts since 1980. As he could not bear to see the wall crumble, Mei regularly patrolled the mountains for the past four decades, trying to prevent damage and safeguard the heritage.

"He started his voluntary patrols in 1980, the year I was born. So ever since I was little, I'd often see him pass by my house after a day of patrolling, and he'd tell me what he saw on the mountains. When I grew older, he'd take me along and tell me about the history and legends of the Great Wall. Over time, I developed a deep affection for it," Liu recalls.

In 2006, Mei consulted with the village committee to establish a voluntary protectors' team, which received enthusiastic support, with more than 40 villagers signing up. Since then, the villagers have been regularly going on patrols to the Great Wall to tackle pollution and damage.

Now, the village has a permanent population of around 130 people, nearly all of whom are involved in the heritage protection efforts, Li says. During these patrols, they'd dispose of litter, remove weeds, pick up and arrange the bricks that became dislodged, and report damage or hazards to cultural heritage authorities.

Liu herself is now a full-time Great Wall protector. In 2019, upon learning about a recruitment drive for Great Wall protectors in Yanqing district, she immediately signed up. After passing a written exam, an interview and a physical fitness test, she became one of the first six individuals selected as Great Wall protectors in the village.

"I remember that on my first day, we went up to the Great Wall and saw a lot of litter, especially plastic rubbish tourists had left behind. We brought our own trash bags and each one of us collected three to four bags," Liu says.

For five days a week, the team members go on a patrol of nearly 20 kilometers, which takes them five to six hours to complete. During their patrols, they regularly take photos of the walls and the watchtowers, especially areas with cracks or fallen bricks, and upload the images to a specialized app linked to the cultural heritage management office of Yanqing district.

"Since becoming a full-time protector, I've noticed that with each trip up the mountain, the amount of litter has decreased, perhaps because of both our collective efforts and growing public awareness," she adds.

Reciprocating the love and care given by the villagers, the Great Wall also brought the village vitalization and prosperity. While the village used to be very poor, with muddy roads and insufficient infrastructure, it has now become a destination for weekend retreats.