A picture says a Great deal about the Great Hall - reference LINK:
https://chicagounionstation.com/information/station-map
Browse around - although realize the information maybe dated -
Which brings up the subject about what entrances are presently
open for access to the Great Hall.
I previously noted the Clinton entrance was closed and directions
to use either of the Canal Street entrances.
Now the Canal entrance(s?) are in a state of renovation ? ? ?
A little help here with the current situation !
The Clinton is now open again ?
The previous aforementioned Adams and Jackson may be
open but handicap/mobility restricted.***
*** Adams Jackson to the Great Hall - not the concession court
east river side of the Train Station
FYI don't be planning on "get me to the church ah er TRAIN on time" !
Get some straight forward (current) information to avoid this !
My last experience was in September - flew into O'Hare - Blue Line
to Clinton - up what seem like a thousand stairs to the street level -
2 an a half block walk to Jackson Great Hall entrance - waited in
Metropolitan Lounge for 3 hours to board #7 (261) private cars -
Escorted to train and on time and on our way !