U of MN Steam Tunnels : East Bank
There is simply no way to do a standard “mission log” type thing for these tunnels.  For one thing, they are too vast and complex to be point-by-point described, and for another, we’ve been there exploring dozens of times, using different entry points and exploring different areas.  So we’ll have to go the general route.
     The steam tunnels run at two levels: there are the deep tunnels, and the shallow tunnels.  Most of the tunnels are at the deep level, which is just above river level.  The shallow tunnels are small isolated networks of about 5-foot high passageways about 10 feet beneath the surface.  You can often see where the shallow tunnels are in the winter when there is just a little bit of snow on the ground, as it will be melted in a broad band above them.  Since the role of steam tunnels is to transport steam (in insulated pipes, of course) from the steam plant to the buildings on the campus, the tunnels which house the pipes are as widespread as the campus itself: the East Bank alone boasts over 12 miles of steam tunnels.

     The East Bank tunnels are anything but uniform.  Built piecemeal over the last god knows how many decades, some of the tunnels are modern, florescent-lit smooth concrete passageways with 10 foot ceilings, while others are barely five feet high, have crumbling ancient brick walls and feature
semi-collapsed side tunnels carved out of naked limestone.  The temperature also varies wildly: some sections are well ventilated to the surface or the cool drainage tunnels and are actually somewhat breezy, while there are other, older areas so hot that you actually have to keep your head down low in just to be able to breathe right. There are also areas that are home to huge orange cockroaches that do not seem to exist at all in nearby sections of the tunnels.

     There are
vertical shafts throughout the system (marked by concentric circles on the map), used both to run steam lines up into the buildings and to vent the hot air out of the system via vents to the outside.  These vertical shafts almost always have ladder rungs sunk into the sides to climb; however, they are disused and thick with clumps of rust, and are sometimes broken.  These lead up into the subbasement of one or more buildings, the surface, the shallow steam tunnel networks, or a mix of the three. Often times water is dripping down from above in the vertical shafts, which makes things rustier and makes looking up as you climb that much less appealing.

     Since open vents means incoming water from rain and snow, there is a drainage system running beneath the steam tunnels, which spills into the Minneapolis drainage tunnels that run just beneath.  If you’re willing to get a bit wet, you can explore the drainage tunnels as well.

     Aside from the tunnels and the pipes, you can expect to find workshop areas, storage tunnels/rooms,
electric cars, and even a few drinking fountains (only 2 of which worked).  If you head northwest far enough, one tunnel actually goes above the surface and comes out outside high above the ground in the middle of some big weird amphitheater-like pit … which was quite a shock the first time for us, as you can imagine.
    In dozens of Action Squads to the steam tunnels, we have never been caught, and have never seen anyone in the tunnels themselves.  However, there are things to be aware of.  First of all, the tunnels are used regularly by maintenance workers, so we only go late at night to avoid bumping into them.  There are also motion sensors in a few places in the tunnels.  They look kind of like garage door openers mounted on the wall or ceiling, and usually have a small red light that comes on when motion is detected.  However, I have a contact in the U of MN security who informed me that when the motion sensors are triggered, they don’t do anything about it because “no one knows how to get down there.”  So don’t worry too much, although you should set them off as infrequently as possible (let them think it was a raccoon or a fluke).  There are a few small elevators that run down into the deep tunnels.  Do not touch them; do not even touch the buttons.  BSAC has monitoring systems separate from the U security, and the elevators are monitored.

     The main security used in the steam tunnels are padlocks.  The surface vents are almost always locked up, but they are worth checking: I know of at least 3 that are never locked.  There are gates at certain places within the tunnels that are sporadically locked: some of them can be
climbed over if needed.  The major entrances and exits are locked up as well.  We have never taken to breaking their padlocks, because it would make it quite clear we’d been there and initiate a security crackdown.  No one wants that.

    Of course, part of the steam tunnel experience is often to get up into the buildings of the campus, and, when possible, get onto the
rooftops.  Security in campus buildings ranges from motion sensors to magnetic door alarms to late-working grad students that will call the police if they see a group of filthy bastards with flashlights creeping about.  Be very alert, very careful, and very quiet if you’re going to get into campus buildings through the tunnels.  Watch for motion sensors.  Don’t turn on lights or use elevators.  If you think you may have triggered an alarm (you won’t hear anything) get the hell out of there fast, and don’t leave any sign you were there.  Decide in advance what you will do and where you’ll go if accosted.  Try to avoid newer buildings, or buildings such as medical centers or computer labs; of course they’re going to have better security.

     By my count, Action Squad has employed at least a dozen entrances to the tunnel systems.  I thought long and hard about whether or not to reveal these locations, and decided not to.  For one thing, part of the fun of urban exploring is finding your way into forbidden places.  For another, the last thing we need is to make it so easy to get into the steam tunnels that any bored frat boy can go online and get step-by-step instructions.  I will, however, write generally about the topic and give some hints that, with the
map, should make it no problem for any reasonably dedicated urban explorer to find a way in.

     There are three basic means of accessing the steam tunnels.  The first is to descend from a building’s basement or subbasement.  If you are able to get into a connected building’s guts, follow the insulated steam pipes back and see if you can find a vertical shaft to climb down.

     The second route is to go in through a
vent cap.  These are distinguished from vertical shafts that do not go to the surface on the map by the circled number accompanying them.  Poke around and you’ll probably find one unlocked.  The tricky part is getting everyone down into them without being spotted.  Decide who is going to lift the vent cap out of the way and go first and who is going to bring up the rear and close the lid behind them.  Wait until no one is around, and do it.  Fast.  Pretty obvious, eh?

     Finally, you can get up into the steam tunnels from the drainage tunnels in a few places.  Look for a grate in the ceiling of the drain tunnel, or a small hatchway.  Push through and you’ll be in the steam tunnels.