Eric Geller uncovers the hidden underbelly of the great cities of the world, not by going to dimly lit criminal hangouts, but by really going underground. As in under the pavement.

On the History Channel’s Cities of the Underworld, co-host Eric Geller explores the modern skyscrapers looming over head and the appearance of the past wiped away, history and forgotten architecture lies just under foot in nearly all the great cities of the world. This series takes the viewer into this hidden world.

The former St. Louisan is one of two co-hosts on Cities of the Underworld which debuted in April and airs Monday nights at 8 p.m. locally. The series explores the architecture, archeology, engineering and history of great cities by taking viewers beneath the pavement. The catacombs of Paris are on their globe-trotting itinerary, which also includes Budapest, Rome, New York and Edinburgh’s hidden sides.

Geller grew up as a congregant of United Hebrew Congregation and is a graduate of Marquette High School and his father, mother and stepfather all still live in St. Louis. “My mother is my best press agent,” said Geller, in a recent phone interview, as the TV host took a vacation in what he called the “wilds of Wisconsin.”

“I always had an interest in history and archeology, but I am not an archaeologist,” said Geller, on his history expertise. “I was a philosophy major at school and I am well-read in Roman and Greek history. If I am an expert on anything, it is on World War I, a special interest of mine.”

On the other hand, Geller has the rugged looks of an adventurer, with his shaved head and close-cropped beard, which was part of what the show’s producers were looking for in a host. “The producers were looking for someone who was interested in the topic and not afraid to get dirty, but they were also looking for someone who was not an expert, someone who would discover this world along with the audience,” Geller said.

Despite his tough guy appearance, Geller’s sense of fun and energetic curiosity quickly come to the surface on the show, and he comes across as an affable fellow on the phone. “I like to have fun, and some people want something more serious.” Co-host Don Wildman takes the more serious side. “We split up the shows. He does a lot of the U.S. sites.”

What set Geller apart for the producers when they were looking for a host was another quality. “My ability to tell a story. They (the show’s producers) wanted storytelling and someone with a certain look. And I had the ability to ask a good second question.” Previously, Geller had worked as a travel writer for Real Edge magazine and has done some acting in independent films.

Which were the most surprising or interesting cities Geller and the series visited?

“I had never been to Rome before. In Rome, you can find complete, intact buildings underground. It was amazing to see a complete fire station, intact and completely buried under the city.” Geller thought everyone should visit Rome in person and while he recommended both shows, he thought the Paris episode was the one not to be missed.

“Between Paris and Rome, Paris was the most fascinating. Paris has hundreds of miles of tunnels underneath it, tunnels no one knows, with bones buried in catacombs.”

“In Paris, there is a Roman village underground, right in front of the Notre Dame cathedral. You can go into it, and it has a nice museum. There is a lot to see (underground in Paris): the sewers and the Roman encampments,” said Geller.

Exploring the sewer systems beneath great cities in Europe has led Geller to one inescapable conclusion. “Sewers all smell,” Geller said.

Nineteenth century Paris was so proud of its modern sewer systems, that Parisians gave tours of it. “Paris has a tour center for its sewer system. They were so proud of it, that ladies in their finery would take tours,” said Geller, referring to Victorian-era tourists. And the smell? “I had hoped the Paris tour would be less smelly, but not so.”

Cities of the Underworld had the highest-rated premiere for a series on the History Channel.

Geller feels that the shows special effects and graphics are one of its best aspects, for its ability to bring the history to life. They also try to keep the show entertaining as well. “It’s educational entertainment,” he said.

The most challenging part of the series is often just getting access to the underground sites. “Shooting the episodes is like making a little documentary,” said Geller. “Sometimes you have limits on what you can cover in a single show.” Time and cost are factors too, as the show’s crew can only spend so much time on site, getting permits, access and shooting, due to funds, Geller added.

Viewers often email the show with suggestions for cities to visit and the producers consider those suggestions. One city Eric Geller would like to explore is Jerusalem. “I would love to do Jerusalem,” he said. “But there is no indication if that will happen. All the history is there but the situation might just make it too difficult or too time consuming.”

Another city Geller would love to see on the show is St. Louis. Caves that once cooled beer and forgotten downtown sub-basements that served as fallout shelters and early subways are among the hidden undersides of our town. “I think St. Louis would make a great show, with the brewery caves under the city and even Meramec Caverns,” said Geller. “There is so much about St. Louis, like the Cahokia Mounds, that is underappreciated and not covered. There is a great story in it.”

Even though he is enjoying working with Cities of the Underworld, Geller has a fondness for his hometown and would like to return to St. Louis at some point.

“I would like to see an educational children’s program out of St. Louis, maybe something with the City Museum. Something fun, like ‘Sesame Street Gone Wrong.'”

“History is just good storytelling. You just need a good teacher to make it come alive,” said Geller. Or a good underground guide.