Nie Zhengyuan gets rid of weeds in the cemetery.

The Red Army Ground graveyard in Tongjiang County, Sichuan province, is home to the remains of more than 3,000 Red Army soldiers. The cemetery has been protected and watched over by four generations of the same family over the course of eight decades.

Most of the soldiers buried in the graveyard lost their lives after getting injured in the civil war. Nie Youkui began to watch over the cemetery in 1934, spending the next 48 years of his life on this voluntary mission. On his deathbed, he told his son, Nie Zhengyuan, that it was the Red Army that allocated farmland to their family and cured Nie Youkui's typhoid. The family could repay their kindness by guarding their graveyard, Nie Zhengyuan's father told him.

Nie stands at the site of a Red Army hospital.

Nie Zhengyuan kept the promise he made to his father and replaced the older man as the defender of the graveyard. Nie Zhengyuan’s son, Nie Changzhou, also chose to continue the mission, opting to work close to home so he could watch over the cemetery.

Every year during Qingming Festival, also known as Tomb-Sweeping Day, both Nie Zhengyuan and Nie Changzhou, along with Nie Changzhou's 19-year-old son and 15-year-old daughter, bring libations and joss sticks to the cemetery to honor the martyrs.