The Battle of Xinkou lasted from Oct 11 to Nov 2. Repeated enemy assaults were repelled, thwarting its aggressive attempts to break through. Whether on the front or in guerrilla warfare behind enemy lines, everyone, from high-ranking officers to ordinary soldiers, fought with unrelenting courage to defend the country, and for national independence and liberation.

"The sacrifices here underscore how hard-won our peace was," Zhao says, adding that this is also the reason why he has taken it upon himself to share the stories of the battle with the next generation, as well as the patriotism and perseverance of those who fought.

Today, the 47 caves — 15 in Hongya Bay and 32 in Hougou — have been restored, their original roles as command centers, field hospitals and stables for cavalry etched into local memory. Since 2015, four major renovations have stabilized the caves using flood barriers.

"The area often experiences heavy rain, which used to cause water levels to rise halfway up the cave dwellings, so a flood control channel was built to help protect them," says Feng Guodong, deputy head of the district's cultural heritage protection bureau. "Now, the site is better preserved."