After Parry recovers from his plastic surgery in Irene's apartment, she removes his bandages and gets to see his new (Bogart's) face. But he doesn't want to put her at risk and decides it's best to get out of her life. He calls for a cab and tells the driver "Post and Fillmore" - the cab drops him off at Harry's Wagon, a railcar diner sandwiched between two buildings.
Then ... These converted railway cars were popular at that time.
... and Now, Sohn's French Cleaners currently occupies the setback building on the site of the old diner, re-addressed as 1919 Post Street.
A suspicious detective apprehends Parry in the diner but he gives him the slip and takes off (below).