Post Office, 8th Avenue between 31st and 33rd Streets.
Update 10/3: There wasn't time for us to show our work in class, but you can view our work here.
Notes from initial stage of observation: We observed the post office after 5, when most others are closed. This is a special one, though - open until 11:59 every night. We took photographs until the security guards got nervous, and video outside.
In terms of the action and flow within the physical space, it seems fairly well designed inside. Some people were confused as they entered, but usually saw the lines or supplies they needed quite quickly. It is a very functional space with no one socializing or loitering. The vast majority of people were alone and had a clear task ahead of them. They knew what they were there for and wanted to do it quickly. Occasionally someone would spread out on a counter and take their time filling out forms or talking on the phone, but they were an exception.
What changed the typical flow is the fact that there's scaffolding all over the outside. This means that there are only 3 entrances as opposed to the usual 8 and the natural flow was perhaps interupted with people more crowded towards the center. See the flow map on the photo page linked to below.
View photos and comments. Video with interviews and more visuals to be shown in class.