Under the pavement of Fujiagou, a small town in the greater city of Chongqing in southwest China, craftsmen and women hustle to produce machinery parts in tunnels that were built as shelter against brutal bombings during the Second Sino-Japanese War.

Chongqing, one of China’s fastest growing municipalities, is home to an array of tunnels built to defend the city—then known as Chung-King—from the hundreds of Japanese air raids that took place from 1939 to 1941. These raids usually targeted residential areas or other non-military marks. It was a campaign designed to terrify the local population into submission.

Now, decades after the war, the tunnels are used in very different ways: as grocery stores, restaurants, and factories.

The average age of factory workers is in the late 30s. Many of the people in the tunnels are sending money to their children so they can get an education and improve their prospects.
The average age of factory workers is in the late 30s. Many of the people in the tunnels are sending money to their children so they can get an education and improve their prospects.

Many tunnels in Chongqing were used unofficially as storage areas and businesses following the war. Now, things are more official. The people working in the tunnels are a mixture of locals from the city and rural migrants who have come to earn money to send home to their families. Those pictured here work in a former Jialing motorcycle factory that now produces machine parts.

Many of the workers in the tunnels are women who share the same accommodation with the men. There is a small wall but for most of the day they gather in the same area to chat and relax.
Many of the workers in the tunnels are women who share the same accommodation with the men. There is a small wall but for most of the day they gather in the same area to chat and relax.
A popular hobby is mahjong, not just with the group of workers but all around China—particularly among the middle to older generations. These men play in one of the bedrooms of the management.
A popular hobby is mahjong, not just with the group of workers but all around China—particularly among the middle to older generations. These men play in one of the bedrooms of the management.

“I came to this place two months ago,” says factory administration worker Chen Wen Yan. “We were colleagues at first, now we feel like family”. Members of the management have their own rooms, but the workers inhabit a room with about 17 people sharing bunk beds.

Members of the management have their own bed space and don't have to share with another employee.
Members of the management have their own bed space and don’t have to share with another employee.
Space is tight and these men share the bottom bunk, leaving the top for their possessions. There is a close bond between the workers, they regard each other “like family”, as one employee puts it.
Space is tight and these men share the bottom bunk, leaving the top for their possessions. There is a close bond between the workers, they regard each other “like family”, as one employee puts it.
Food for the workers is high quality, with most of the ingredients locally sourced. All made fresh on a daily basis.
Food for the workers is high quality, with most of the ingredients locally sourced. All made fresh on a daily basis.

The days are long and the pay is low compared to the average city wage. Signs placed by factory bosses highlight the need for care in the tunnels, but workers wear little to no protective clothing save for face masks and overalls with cartoon animals.

Shu is one of the many employees who works without protective equipment in the tunnels.
Shu is one of the many employees who works without protective equipment in the tunnels.
Working in the tunnels can be treacherous without protective gear.
Working in the tunnels can be treacherous without protective gear.
In the factory’s quality-control area, a worker checks the dimensions of the parts produced in the tunnels.
In the factory’s quality-control area, a worker checks the dimensions of the parts produced in the tunnels.

But the days of working in these conditions are coming to an end. The local government has already closed over half of the tunnels in the area, to be converted into a museum and memorial for the war and it casualties. In 2017 the whole area will be transformed to accommodate, not workers, but tourists eager to see the battleground that survived the onslaught of war, then helped to rebuild industry.