Dr. Jeffrey Gusky is one of few people other than local landowners who have seen the artwork carved by WWI soldiers on the walls of vast quarry systems throughout France, beneath the trenches that defined the so-called "Great War."
These underground cities — often outfitted with telephones, electricity, theaters, hospitals and even street signs — were home for months on end for soldiers on both sides as they engaged in the bloody warfare on the western front of the war.
"These were the only places where they could find shelter," Gusky told Here & Now's Meghna Chakrabarti. "There were stairways to hell connecting these underground cities to the trenches. These were places where they could be human. So there's hope here — this is a story of hope."
Gusky, who is also emergency room physician in Dallas, photographed "The Hidden World of the Great War" for the August issue of National Geographic magazine.
On the art he found underground
"The most remarkable part is the art and the emotional graffiti inscribed in stone by soldiers one hundred years ago."
"It's amazing. You cannot believe. Some of it's very sophisticated — you find art that looks like Picasso, but Picasso was only 20 years old at the end of WWI. You find classical Greek-looking art. You find primitive, you find contemporary, you find folk art. And then there are the inscriptions — these emotional messages to the future that tell us I once existed, I was here, I'm a living breathing human being. It's very emotional because when you're standing in these places in complete darkness and your headlight shines on the wall, you see something that no one has seen before or that few have seen. It's been untouched for a hundred years; it's like one hundred years is yesterday."
On the differences between the caverns and tunnels
"The tunnels were dug new during the war and they're crawl spaces most often, used offensively. They don't have art or living quarters or the infrastructure of a city, whereas these places were large. I'm talking really large. One place I photographed had 18 miles underground, in one place. These places are very stable — you can walk around in them once you get inside. Sometimes you have to climb in through a tiny hole. Some of these places are quite treacherous; there are live rocket shells, hand grenades, bullets on the ground. It's like walking into a time capsule."
On why the cities are still relevant today
"They lived underground, and then they would go up to the trenches and fight and then disappear back under the earth. These were modern people — they lived in high rises, they drove cars, they went to work on subways, they watched movies — and they were inundated with mass media and messaging just like we are today. They show us how we can push back against the inhuman scale of modern life. This is the importance of this discovery to me, and this is the emotion that I feel when I'm down there. They really are us. In many ways, 2014 is very similar to 1914."
This segment aired on July 25, 2014.