Two feet beneath the grass of Tercentenary Theater, maintenance workers check pipes and pressure gauges in perfect quiet as the voices and heat of the University rush overhead.

Under Mill Street outside Winthrop House, two carts pulling trailers full of salad, soup and uncooked lasagna pass each other with the whirr of electric motors.

At the core of the Weeks footbridge in a three-foot crawlspace, three steam pipes make the temperature close to 100 degrees for workers crawling through to the Business School.

Just underneath the sidewalks, classrooms and bedrooms of the University is a system of walkable passageways, bringing light, heat, communications and sometimes food as far north as the Law School and as far south as Peabody Terrace.

Welcome to a world of utility and rumor. Welcome to the tunnels-Harvard's underground.

Steam Tunnels

The University relies on centrally distributed steam to heat the majority of its buildings. The steam that heats every room in the river Houses and the Yard starts out two blocks past Peabody Terrace, in a plant run by the city of Cambridge.

An existing network of steam tunnels was extended to this site in the early '20s, with an extension to the Business School-disguised at the hollow center of the Weeks Bridge-laid in 1926.

In their current form, the tunnels leave the steam plant, pass in front of Mather and Dunster houses in the Memorial Drive sidewalk and then head under Old Leverett to Mill Street.

From Mill Street, tunnel spurs take steam, power, telephone and data lines to the other houses along the river, but the main line runs under Lowell House and up under Linden Street to the Yard.

After shrinking to another crawlspace as it passes over the Red Line under Mass. Ave., the tunnel branches under Wiggles worth Hall, with spurs and impassable buried lines covering all the Yard buildings.

North of the Cambridge Street overpass, where it is again impassable, the tunnel then links the Science Center with the Law School, Divinity School and Biological Labs. In all, there are 3.5 miles of walkable tunnels beneath campus.

The tunnels vary in size, but most are about eight feet square, with 12- and 10-inch steam pipes along each wall-their 380 degree-plus surface temperatures dulled by four inches of insulation. Inside steam rushes by at 100 pounds of pressure. Overhead are the black cables that bring the University power and communications ("We don't have telephone poles," says Secretary of the Faculty John B. Fox Jr. '59), and underfoot is brown residue from shallow pools of groundwater.

"It's a pretty unglamorous place," says Michael N. Lichten, director of the Office of Physical Resources in the Faculty of Arts and Sciences (FAS). "In some ways it's like going into a mine."

During the winter, when each of the three steam pipes hits 430 degrees, the temperature in some parts of the tunnels can climb past 100 degrees.

"It's kind of like a cool steam bath," says Harry A. Hawkes, director for engineering and utilities, who oversees the tunnels' operation most directly.

Excess heat in the tunnels is vented out through above-ground vents "mushrooms" to tunnel workers-of which the most visible is located next to a path outside Canaday Hall.

However, on some occasions the tunnels can still be dangerous. Last Monday, a steam pipe-gasket leak in the Yard flooded the tunnels in that area with steam and short-circuited the lights, leaving tunnels from the Science Center to Widener Library completely blacked out.

"It's not so hot [that] it's uninhabitable, and the tunnels are well-ventilated," Hawkes says, but adds, "absolutely we send people down there in pairs."

Underground Round

Another tunnel system was built around the same time that the steam tunnels were extended, linking a central kitchen under Eliot House with smaller "finishing kitchens" in Eliot, Kirkland, Lowell, Winthrop and Leverett houses.

Running parallel to a steam tunnel spur for most of its length, the dining-services tunnel is about eight feet high and 15 feet wide.

According to Robert J. Leandro, assistant director of house dining, traffic in this tunnel starts about 6 a.m. Food and other supplies are packed onto the long beds of the electric carts, or into warming and cooling trailers, and then trucked off to House kitchens for breakfast service.

"They start delivery at 6 [a.m.], and don't stop until dinner, because every bit of trash has to come back to the central kitchen," Leandro says.

"It's amazing how much stuff goes down there."

In the white-walled, well-lit tunnels-"they look better than one would think," Leandro says-trucks move stacked with bagels and trailers filled with pre-made salads, soups of the day, and "assembled" but uncooked lasagna.

Dining Services maintains a fleet of Crimson William Decherd UNDERGROUND ODYSSEY: A worker attends a steam plant near Peabody three 10-foot carts-"like golf carts, only a little more heavy-duty," says John J. Mingle, food service supervisor at the College dining halls-and upwards of 10 warming and cooling trailers, all run off battery power.

Leandro estimates that the average-travel time for bagels and other food headed to the Leverett kitchen is about a minute and a half.

"It all happens pretty quick," he says. "It's actually pretty cool."

Rumors Abound

Harvard underground is a world with its own mythology-rumors about crimes committed and escapes made through these tunnels just below the corridors of power.

Then-Associate Dean of Freshmen W.C. Burriss Young '55 told The Crimson in 1993 that former Alabama Governor George C. Wallace escaped an angry crowd at the Law School in 1968 through the tunnels.

Author Jane Langton, in her 1978 The Memorial Hall Murder, says Henry A. Kissinger '50 avoided an anti-war protest by leaving the Law School through the tunnels after a Vietnam-era speech.

Fox says he thinks former Secretary of Defense Robert S. McNamara might be a more likely candidate.

Young also said in 1993 that former Harvard Police Chief Robert Tonis, while serving as an FBI agent in 1939, lost track of a suspected Nazi spy when he disappeared into the tunnels through a River House.

Neither Lichten nor Hawkes would confirm that the tunnels had ever been used to move VIPs between buildings, but both agreed that such a move would be possible.

"It's possible to take someone from building-to-building through the tunnels, but it hasn't been done recently," Hawkes says. "I've heard the stories."

Rumors also abound about student forays into the tunnel system-currently illegal outside of WHRB radio personnel who use tunnel wiring with official permission.

Tunneling stories usually begin in first-year dorms, where tunnel doors are often more accessible than in upper class Houses.

"We just went exploring a couple times," says a junior in Winthrop House of his first-year tunnel experiences. "The funny moment came when we realized we were tripping alarms all along the way-which we realized 15 minutes after the first alarm.

"There's a big vent by Canaday, and we climbed up there and were watching people walk by."

A sophomore in Pforzheimer says she made it to the basement of Canaday Hall through the tunnels last year, and returned with a haul of comfortable chairs for her room.

As of this summer, Hawkes says all of the tunnel doors are alarmed, with the alarms registering in a 24-hour central engineering control room deep under the Science Center.

Alarms tripped at night mean a call to the Harvard University Police Department (HUPD), with an engineer meeting an HUPD officer near the alarm site and descending into the tunnels.

Dean of Students Archie C. Epps III says that students have been caught in the tunnels in the past, but that students illegally enter them "rarely, and certainly not recently."

"We take [students' entering the tunnels] very seriously," Epps says. "I don't suggest that anyone try."

Tunnels can in some places be extremely hot, according to Lichten-"hot enough so that you could conceivably faint or get disoriented."

"It's a dangerous place to be if you're alone. There's a lot of high temperatures and lots of equipment," he says. "It's really just not a safe place to wander."

In Langton's book, the tunnels are used by the cronies of a fictional University President to plant dynamite under Sanders Theatre, and to poison a Sanders audience with carbon monoxide in the air ducts.

HUPD spokesperson Peggy A. McNamara says that in 1995, the tunnels were utilized in a real crime, a late-night burglary of two campus buildings. She would not release the names of the buildings.

Despite their checked past, the tunnels' mystique seems to be somewhat lost on Hawkes and Harvard's engineers, for whom the legendary Harvard underground is just a workspace.

"To us they're just utilitarian-we have a job to do in them," he says of the tunnels, but admits that he could see why some would be interested in them. "They're a part of this place, and a part of what makes this place work.