From 1970 to 1998, there was always what appeared to be some kind of tower, or a building that sat directly behind the carriage house in the arbor, this building always had the alphabet painted on the exterior (well, all we could make out were AB and DE, though in its earliest incarnation, we could also see the edges of a C and an F), from 1970 to 1989 it simply painted as part of the flat behind the arbor fence, but by 1990 it was built-up and was an actual structure; from 70 to 93, it was red, but from 94 to 98 it was gray.
I've come up with a theory as to what that building might have been... all these years, I assumed that the letters we saw painted on it was grafitti, since it wasn't uncommon to see letters and numbers as grafitti on Sesame Street, then I got to thinking about how the earlier red version reminded me of how YEARS ago when I was a little kid, we had a small factory on the edge of town, and half of the factory building (which had no windows or doors or anything at the time) was painted over with grafitti, and almost made it look like a giant candy wrapper or something... and then it hit me... suppose this structure we saw behind the carriage house from 1970 to 1998 was a factory as well, and perhaps the letters on the exterior weren't grafitti, but maybe representing that the factory manufactured letters? After all, everybody on the street seemed to have a steady supply of letters back then, like when Kermit got attacked by a W, when Big Bird stepped on the J that was in his nest, etc... maybe THAT'S where they got their supply of letters from?
I've come up with a theory as to what that building might have been... all these years, I assumed that the letters we saw painted on it was grafitti, since it wasn't uncommon to see letters and numbers as grafitti on Sesame Street, then I got to thinking about how the earlier red version reminded me of how YEARS ago when I was a little kid, we had a small factory on the edge of town, and half of the factory building (which had no windows or doors or anything at the time) was painted over with grafitti, and almost made it look like a giant candy wrapper or something... and then it hit me... suppose this structure we saw behind the carriage house from 1970 to 1998 was a factory as well, and perhaps the letters on the exterior weren't grafitti, but maybe representing that the factory manufactured letters? After all, everybody on the street seemed to have a steady supply of letters back then, like when Kermit got attacked by a W, when Big Bird stepped on the J that was in his nest, etc... maybe THAT'S where they got their supply of letters from?