Q: If my Metro North train is on the underground level, why do I have to go to street level from the (underground) subway, only to descend again for my Metro North train? Shouldn’t I be able to stay underground when going from the subway to the Metro North?
 
A: Well, if you think about it, you do stay underground for some of the transfers. To get from the Shuttle platform into Grand Central, for example, one only ascends a single stretch of stairs to reach the western corridor into the upper concourse and the Metro North tracks—and you remain underground the entire time. 

But, yeah, okay, I’m being an annoying shit—you’re talking about the 4, 5, and 6 subways, aren’t you? You want to know why in hell does the MTA send you all the way up to the street level merely to prolong the Bataan Death March back down to your Metro North train?

Good question. But let me split just one more hair before I answer you. If you’re talking about transferring from the 4, 5, and 6 trains (a/k/a the Lexington Avenue Line) to Grand Central’s upper-level tracks, you are pretty much being sent no higher than you have to be. The upper-level commuter tracks lie at the bottom of a very gentle slope off the terminal’s main concourse—and the concourse level is exactly as high as you climb (from platform up to mezzanine, then from mezzanine via escalator to the eastern corridor of the terminal) as you leave the subway. 

But if you’re talking about getting off the subway and hoofing it for a Metro North train on the lower-level tracks, well, I feel your pain. Your aching knees, specifically. Why do you have to go up to go down? Isn’t a more direct connection possible? 

Short answer: No—There’s too much shit in the way. 

Long answer: No—now, proceed with below. 

Let’s just establish some parameters first—with the understanding that the figures I furnish are merely estimates. Here are some fun facts for your next commuter cocktail party:
* Grand Central upper level tracks:­ 1 story down (about 20 feet)
* Grand Central lower level tracks:­ 2 stories down (about 60 feet)
* Subway Shuttle: 2 stories down (about 50 feet)
* Subway 4, 5, and 6 Grand Central station:­ 2 stories down (about 50 feet)
* Subway No. 7 Flushing Line is one deep-ass train—about 80 feet below the street—and too far below Metro North’s tracks to make it useful to include here. 

Now, I’ve already dealt with the Shuttle so we’ll leave that out. Let’s look at the Lexington Avenue Subway—how deep it is, and also where it is. First, the terminal’s lower-level tracks and the Lexington Avenue Subway trains are almost exactly at the same depth: Score 1 for your argument that there really ought to be a straight-line connection without ascending to street level. 

Second, Grand Central platforms of the 4, 5, and 6 trains are actually built on a 45-degree diagonal relative to the avenues. (This is, incidentally, because the Park Avenue portion of the subway opened in 1904 but the Lexington Avenue extension north was not opened until 1918. The subway had to literally move over from Park Avenue to Lexington, and that connecting stretch was where the subway station was put in.) The 4, 5, and 6 stop for Grand Central roughly cuts diagonally beneath the southeastern corner of the Terminal proper—in easy reach of the commuter tracks toward the terminal’s eastern side: Score 2 for your argument. So, again, why the hell isn’t there one? 

As referenced above: There is too much shit in the way. If you were to try to dig a passage leading from the 4, 5, and 6 platforms right into, say, the general area of Tracks 101 – 103 on the terminal’s lower level, you’re talking about having to cut through the foundation walls of the old Commodore (now Grand Hyatt) Hotel, a task made more nightmarish by the tightly-spaced grid of support columns—needed to carry the weight of the building above—that run the length of the subway’s platforms. But okay, say that you somehow manage to snake some stairs around all those girders and I-beams. Next, you’d have to blast through the foundation wall of Grand Central Itself. Such a thing is possible, I suppose—but, finally, you’d run into the figurative boulder that cannot be moved. 

When the railroad’s chief engineer William J. Wilgus planned out the track arrangements for the new Grand Central Terminal in 1903, he had to find a way to turn trains around quickly within the tight confines of its interlock. Wilgus did this by designing loop tracks on both levels. The loop tunnels curve around below the terminal’s façade, connecting the westernmost and easternmost tracks in the shape of a large horseshoe [for more about the loops and how you can experience them with family and friends, refer to the Engine Bob installment that immediately precedes this one.] Those loops are not as quaint as they sound; they’re massive tunnels, two—and in places three—tracks wide, with massive load-bearing walls enclosing them on both sides. There is no conceivable way that the terminal could ever sacrifice the operational advantage of the loop tracks (much less run up an expense that would rival the gross national product of France) by ramming a pedestrian passageway through them. And because the loop is two-stories deep and swings to the laterally widest points of the terminal’s track grid, there’s simply no way around them. 

Other, that is, than being led above them, then back down on their other side—which is exactly what you are made to do right now.