39 Things You Probably Don’t Know About The Old Main Post Office

The Old Main Post Office

The Old Main Post Office

With the Old Main Post Office in the news these days, we thought it was a good time to set the Wayback Machine for the mid-1930’s and take a closer look at the building that these days causes so many people to avert their eyes.

  1. Cost: $21 million
  2. Length: 800 feet
  3. Width: 350 feet
  4. Height: 230 feet
  5. Floor space: Three million square feet.  Ish.
  6. At the time of its completion, this was the largest post office in the world
  7. At the time of its completion, this was the largest American government building outside of Washington, DC
  8. Maximum capacity (1943): 19 million letters per day
  9. By 1967, the building handled an average of 21 million letters per day
  10. Peak hours were 3:00pm-9:00pm
  11. Each cancelling machine could frank 36,000 letters an hour (1933)
  12. The amount of mail handled each year could fill the entire volume of the building four times
  13. When the design of the post office was revealed, it was considered a big surprise.  Most people expected the building to be a two-story building with offices on the second floor, and sorting on the first.
  14. The building was designed as a high-rise to save money on land costs.
  15. The Treasury Department, which was in charge of the Department of the Post Office at the time, didn’t like the high-rise idea and fought to have a more traditional post office built
  16. Washington bureaucrats didn’t want the Post Office to be built at the intersection of Halsted and Congress.  It was the Commercial Club of Chicago that convinced Postmaster General Frank Hitchcock and Postmaster Daniel Campbell to locate the building in compliance with the club’s beautification plan for Chicago.
  17. The Post Office wasn’t built just because the old building ran out of capacity.  The old building was in terrible shape.  Because it was built on a wooden foundation which rotted quickly, within two years of opening the old building had sunk 14 inches into the soft lakefront dirt, and many of its walls were leaning.  An emergency concrete foundation had to be built to keep the building operational.
  18. “Motor trucks, one every minute, will bring in letters from collection boxes throughout the city.  These letters will be shot upward in elevators to the upper floors, and travel by gravity down through the building.  By the time they reach the ground floor they will be canceled, sorted, and ready for dispatch by train or airplane” —Popular Science, August 1931
  19. When the post office opened, inbound packages were sorted into the following conveyor belts (incomplete list):
    — City
    — Illinois (cities A-L)
    — Illinois (cities M-Z)
    — Wisconsin (cities A-L)
    — Wisconsin (cities M-Z)
    — Indiana
    — Iowa (cities A-L)
    — Iowa (cities M-Z)
    — Ohio
    — Pennsylvania
    — California
    — To The West (1)
    — To The West (2)
    — To The Southwest
  20. Outbound mail was sorted onto the following conveyor belts to be shuttled across the city:
    — City
    — Union Station 1
    — Union Station 2
    — Union Station 3
    — Illinois Central Station
    — Dearborn Station
    — Northwest Station
    — B&O Station
    — Miscellaneous
  21. Outbound mail then came off the conveyor belts and slid down a spiral slide to the loading platforms
  22. On May 15, 1938 the first mail was transferred from Chicago Municipal Airport (what we call Midway) to the downtown post office by an autogiro.
  23. The rotary aircraft landed on a 3,000 square foot runway built between the two penthouses on the south end of the roof.
  24. It took 17 minutes to carry the 138 pounds of mail by air through a hailstorm to downtown. The same trip by truck would have taken 90 minutes.
  25. In August, 1949 the Post Office began regularly transferring mail by helicopter between the airport and the Main Post Office.  By November, helicopter mail transfer service was expanded to 44 Chicagoland and Northern Indiana suburbs.
  26. In 1936 a water main break filled the lower level of the building with seven feet of water.  Workers managed to rescue most of the mail before it could be saturated.
  27. In 1963 a leak in a tunnel running beneath both the Chicago River and the Old Main Post Office sprung a leak and shut off the building’s telephone service.  The tunnel is 40 feet under the river, six feet tall, six feet wide, and 1,150 feet long.
  28. The Post Office garage (northwest corner of Polk and Canal) cost just under two million dollars ($1,960,000)
  29. The Post Office garage was designed to store and service 550 trucks at a time
  30. Before it was even built, the Post Office garage was outdated; the Chicago Post Office had over 770 trucks by then
  31. When the Post Office garage opened, it included a “blacksmith’s shop,” which we hope meant welding or fabricating, not shoeing horses
  32. In June, 1981 a security guard was gunned down at the Old Main Post Office
  33. There used to be public tours of the Old Main Post Office.
  34. You used to be able to pay a “special handling” fee to have your package sorted by an actual person instead of the conveyor belt system
  35. In the days of hand-sorting, mail with insufficient postage, illegible addresses or other problems were known as “nixies” and went to a special department for further handling
  36. For some reason a lot of mail addressed to “Westmore, Illinois” would arrive at the post office.  It automatically went into the “Nixie bin” because there is no Westmore, Illinois.
  37. According to the Chicago Tribune, one letter that landed in the Nixie bin was addressed simply “That Dirty Word Hotel, Chicago.”  The postmark was Atlanta, so the letter was sent on to the old Sherman House Hotel.
  38. The deadline for sending Christmas cards to servicemen during World War II was October 14th.  During the war in Afghanistan it was December 4.
  39. There was once a plan to redevelop the Old Main Post Office in time for the 1992 Chicago World’s Fair, which also never happened
The Old Main Post Office

The Old Main Post Office

Location: 433 West Van Buren Street, West Loop

Author: Editor

Editor founded the Chicago Architecture Blog in 2003, after a long career in journalism. He can be reached at chicagoarchitectureinfo@gmail.com.

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