Three people wearing waders and headlamps climbed out of a sidewalk manhole on Seventh Avenue directly across from Pennsylvania Station on Aug. 18, and the footage of them stepping onto a Midtown Manhattan sidewalk has since ricocheted across social media, spawning theories ranging from scavenger hunts to secret underground societies. Nobody in an official capacity has said the group posed any danger to the public, but nobody has fully explained what they were doing down there either.
A Sighting That Wouldn't Stop Spreading
According to The New York Times, a second person in waders and a headlamp emerged from the same sidewalk sewer on Seventh Avenue, and the footage of the scene was shared widely online, spawning rumors of an underground society living beneath the city. The paper reported it was the fourth known episode of people entering or leaving city maintenance holes since May, though a separate account from mk.co.kr put the tally at five such sightings since May — a discrepancy that remains unresolved. Bloomberg, which reported on the Penn Station sighting, tied it to the area near a hotel where Israeli Prime Minister Benjamin Netanyahu was staying, according to Bloomberg.
Online forums lit up almost immediately, floating a grab bag of explanations for who these people were and why they were surfacing in one of the busiest transit hubs in the country. Some commenters guessed they were urban explorers chasing an adrenaline rush underground, while others suspected they were influencers hunting for viral content, or scavengers hoping to snag valuables that had slipped through street grates over the decades. The chatter escalated into full-blown mythmaking, with some forums dubbing the group “mole people” and others invoking the Teenage Mutant Ninja Turtles as a point of comparison.
NYPD Reviewing Footage, No Sign of a Threat
Investigators have not landed on an answer either. Per a report examining the video controversy, the NYPD said investigators were reviewing surveillance footage in an effort to identify the three people seen near Penn Station, and authorities had not announced any evidence that the group was conducting surveillance, preparing sabotage or planning an attack. Detectives reportedly believe many of the people caught entering the sewer system are searching for objects of value that fell or washed underground, rather than pursuing anything nefarious.
That assessment lines up with reporting from NBC New York, which described video showing groups pry open manholes and climb into the sewer system for three consecutive days in Brooklyn and Queens. Law enforcement sources told the station it did not appear to be nefarious, though there was still no clear answer as to why the people kept going underground. The station's report noted that some of the groups spent up to three hours down there at a stretch.
A Pattern Stretching Back to May
The Penn Station sighting was not an isolated event. The same report on the video controversy noted that four arrests followed earlier incidents in Williamsburg and Gravesend in May, with those detained telling investigators they had gone underground to scavenge for valuable items. In late May, roughly seven people reportedly entered a manhole in Gravesend and apparently spent about three hours beneath the streets before resurfacing.
More recent incidents have also led to arrests, though accounts of the charges conflict. The Times reported that officers arrested two men in July who they said were sewer diving in Brooklyn, charging them with criminal trespass, while mk.co.kr described two men arrested that same month and charged instead with home invasion. Separately, NBC New York noted that three men were charged with burglary and other counts last year after they went searching for gold, jewelry and other valuables in a Brooklyn sewer.
What Makes the Underground So Risky
Officials have repeatedly warned that the city's sewer system is not a place for casual visitors. NBC New York reported that seasoned explorers typically bring gas meters to check for dangerous fumes, including potentially flammable hydrogen sulfide, and that the tunnels are humid, slippery, and can carry pathogens along with flowing wastewater. Estimates of the network's size vary: the Times put it at roughly 7,500 miles of pipes, NBC New York cited 7,400 miles, and mk.co.kr described a network extending about 12,000 kilometers.
Long before this summer's viral clips, the city's underground had already drawn its share of dedicated chroniclers. NPR once followed urban explorer Steve Duncan, who examines the hidden tunnels, subways and sewers of major cities, on a 25-mile journey beneath New York alongside Norwegian explorer Erling Kagge — the pair emerged from a previously scouted Bronx manhole just after 5 a.m., filthy and elated. Whether the trio near Penn Station shared that spirit of exploration, or something else entirely, is a question the NYPD says it is still trying to answer.
