By Jared Ebersole in Video — 14 Mar 2026

The Holland Tunnel's Ugly Towers Are Its Lungs

The Holland Tunnel could not exist without its ventilation towers. They solved the carbon-monoxide problem that made long car tunnels seem impossible.

The Holland Tunnel's most important architecture is not under the river.

It is the pair of odd, blunt ventilation towers sitting in the Hudson, plus the matching land towers on each side. They look like leftover utility buildings because that is what they are. They are also the reason the tunnel could be built at all.

Where it is

The New York land ventilation building is at 423 Canal Street, New York, NY 10013. The river towers sit offshore in the Hudson River between Manhattan and Jersey City.

Before the tunnel, crossing the Hudson by vehicle meant ferries. The river was crowded, slow, weather-exposed, and increasingly inadequate for a region that was growing around automobiles and trucks. A bridge was considered, but a bridge into lower Manhattan would have required enormous land acquisition for approaches. Dense city blocks are not friendly to long ramps.

A tunnel looked cheaper and cleaner on the map.

Then engineers faced the problem that made the map almost meaningless: exhaust.

Rail tunnels already existed under New York's waterways, but electric trains did not create the same carbon-monoxide problem as gasoline cars. A long vehicular tunnel under the Hudson would trap exhaust in a tube with drivers, passengers, workers, heat, smoke, and very few easy exits. In the 1920s, carbon monoxide from automobile exhaust was not a background nuisance. It was the central life-safety problem.

Thomas Edison reportedly doubted that a tunnel of this kind could be ventilated safely. Whether quoted as prophecy or skepticism, the objection was reasonable. The obvious method, blowing air from one end of the tunnel to the other, would have required huge air speeds and still left dirty air traveling along the roadway with the traffic.

Ole Singstad's solution was transverse ventilation.

Instead of treating the tunnel like one long pipe, the design split airflow into layers and sections. Fresh air entered through ducts and curbside openings along the roadway. Exhaust was pulled up through openings in the ceiling and carried out through separate ducts. The tunnel did not have to wait for air to travel from portal to portal. It could breathe all along its length.

That idea had to be proved before anyone trusted it with human lives.

The U.S. Bureau of Mines, universities, and tunnel engineers ran extensive tests, including work in a more than 400-foot experimental tunnel at the Bureau of Mines site in Bruceton, Pennsylvania. Cars were operated under controlled conditions, carbon monoxide levels were measured, and people were exposed under supervision to study tolerable limits and ventilation performance. By modern ethical standards, the idea of college students breathing exhaust as part of tunnel testing lands differently. At the time, it was part of the research that made the system credible.

The final system was enormous.

The four ventilation buildings housed 84 fans: 42 blowing fresh air in and 42 exhausting dirty air out. The American Society of Mechanical Engineers describes the fans as capable, at full speed, of completely changing the air in the tunnel every 90 seconds. The Port Authority's own history describes the system as a set of intake and exhaust ducts served by adjustable-speed fans, with land and river ventilation buildings on both the New York and New Jersey sides.

That is why the towers look so uncompromising. They are not decoration. They are machinery scaled up to architecture.

When the Holland Tunnel opened in 1927, it became the world's first mechanically ventilated underwater vehicular tunnel and a model for later car tunnels. The ventilation system was not a supporting feature. It was the breakthrough. Without it, a Hudson River car tunnel would have been a carbon-monoxide chamber with toll booths.

There is a quiet lesson in the ugliness.

Cities often hide the systems that make them usable. Water comes through pipes. Electricity arrives from substations. Trash leaves through logistics nobody wants to watch. The Holland Tunnel does the opposite. Its lungs stick out of the river, too large to ignore, reminding everyone that infrastructure is not only movement. It is air, safety, maintenance, and the unglamorous physics of keeping people alive inside a machine.

The towers are not pretty.

They are breathing for the tunnel.