The rear one is a reserved parking, with a Govt. of Canada sign post. But on the intersection of these two streets, you can see two boxes, one big black, and the other two small red ones (see picture). These seem to be mail boxes (for outgoing most likely, and may be incoming too).Oscar7 said:This building is at the intersection of Dorchester Street and Charlotte Street, and if one moves a little on Charlotte Street you will see the back side of this building where the parking lot (for this building) is. That should probably also be the entry for the mail room I am guessing (which means that's where the courier trucks must come).
As you correctly pointed out, plus the road at the front (Dorchester Street) not being super wide, it doesn't seem like a good idea for delivery trucks to block traffic on this road!
The building in front of the CIO building is Bank of Montreal (right side in this picture), and is more architectural. That's how these old time banks usually are anyways.
Regards