The Jiaozhuanghu tunnel may have seen more than 150 battles during the second world war but it has attracted precious few tourists in the 60 years since.
However, a tunnel museum, established in 1987, has seen thousands of visitors a day in the lead-up to the 'golden week' holiday that kicked off on Sunday.
The site, about 60km north of Beijing, is a 23km underground network of tunnels equipped with shelters and command posts.
The surge in visitor numbers has been attributed to a central government drive to encourage 'red tourism' that coincides with this year's 60th anniversary of the end of the Sino-Japanese war.
'Our museum has seen a marked increase in the number of visitors since March after a five-year national campaign for red tourism was kicked off early this year,' said tour guide Wang Jinxia .
Ms Wang, a 36-year-old local who has been working at the museum since it opened, said most visitors were either members of the party or students.