Underneath Andover: Investigating the Mystery Surrounding the Heating System’s Tunnels

Beneath Andover’s historic campus lies a system of tunnels and steam pipes. Characterized by high temperatures and voltage lines, most tunnels are now out of use. Currently, the only known and accessible tunnel is located between the basements of Pearson Hall and Morse Hall.

Although students once accessed the tunnels, according to a 2005 article in The Phillipian, the administration has since removed many of them due to safety concerns. According to Joshua Mann, Instructor and Chair of the Classics Department, these tunnels likely formed a network that connected multiple buildings in the Flagstaff and Greener Quad. Mann mainly believes that the tunnels were constructed for utility purposes.

“As far as I know, I think [the tunnels] were two things. First, I think they were utility tunnels to service the steam pipes or the heating systems between the guts of the buildings… Now I think they continue to be that but some of them are obsolete or out of use… Sometimes you can see, especially this time of the year on campus, where a lot of the steam pipes exist because the snow melts there first. Anytime you see some green poking out, where otherwise it would be white, that’s part of the heating system,” said Mann.

Mann continued, “There was a point where [the Pearson-Morse tunnel] was used as a riflery range, when we had people who did those kinds of things. It makes sense, it is a really straight, long tunnel so I could see them using it that way.”

Paige Roberts, Director of Archives and Special Collections, hypothesized these tunnels were built in the late 1920s when Thomas Cochran, Class of 1890, funded an immense, campus-wide reconstruction project. Due to the scale of this initiative — involving the demolition, renovation, and construction of multiple buildings — Roberts suspects that it featured the implementation of new heating, ventilation, and air conditioning (HVAC) systems as well.

Mann, who has previously entered the tunnel connecting Pearson and Morse, described past visits to the tunnel with Seniors. Although students seem to exhibit particular excitement towards the tunnels, Mann emphasized their normality. Despite rumors, the tunnel is now only used as a storage space and hosts parts of the heating system.

“The one I am often asked about is the tunnel that connects Morse to Pearson because that is in the basement. Usually when students are Seniors, [for] those who want to go see it, usually in the spring on an afternoon, I open it up and we go down. I always think it is very anticlimactic because it’s really just a tunnel, but I think the students get a kick out of it, so I have no problem doing that,” said Mann.

Although Mann has heard about other tunnels in Flagstaff, he has not been able to verify their existence. Mann also speculated that during the mid-twentieth century, during the Cold War and the nuclear age, many campus buildings hosted basements designed to function as nuclear fallout shelters.

“I’ve just heard about [tunnels] that connect some of the buildings that are on the central Greener Quad, whether it is dorms like Foxcroft or [Samuel Phillips Hall] and George Washington [Hall]… I know also that, or I suspect that, during the mid-century of the twentieth century, because of the Cold War and the nuclear age, a lot of these buildings had basements that served as nuclear fallout shelters,” said Mann.

Ruth Davis, member of the Office of Physical Plan (OPP), described how the intriguing tunnels are actually part of an underground steam system that is solely accessed for maintenance on underground piping. Despite the tunnels being rumored as possibly connecting different buildings in Flagstaff Cluster, Davis noted that the tunnels are instead ‘larger concrete structures’.

“Our underground steam system comprises miles of underground piping, and is direct-buried, enclosed in concrete trench boxes, or – in very limited areas – enclosed in larger concrete structures that we refer to as tunnels but are likely not the kind of tunnels you are envisioning. They do not connect buildings but rather enclose this critical infrastructure and allow limited access for maintenance. These tunnels are remotely monitored for safety reasons. As mentioned earlier, we do not believe there are underground tunnels that connect campus buildings,” wrote Davis in an email to The Phillipian.

In addition to hearing rumors of the tunnels’ existence, Shixun Song ’26 described how he discovered similar tunnels in Graves Hall. Regarding the tunnels as a part of campus history, he hopes for increased student interaction in the future.

“I heard about the tunnels in my Freshman year when Mr. Mann mentioned that there were tunnels underneath Pearson [Hall] connecting to Morse. I also saw trap doors leading to tunnels in Graves Hall… I did peek into the Graves Hall tunnels once. It was just a maintenance tunnel, but I still think it was pretty cool… I know they’re closed off now, but I think it would be really cool if [the Office of Physical Plant (OPP)] could allow more student trips, granted that they’re led by adults… It’s a part of our history, it’s a cool feature of our campus,” said Song.