I think by the 1970's very little in the way of manufactured

goods were shipped in break bulk ships.  By then break bulk would be things like lumber, coal, grain, steel, or anything that would be shipped in a covered hopper.  I think some heavy equipment came in or went out on break bulk ships, but any sort of small manufactured goods like electronics or auto parts would have been shipped in containers.  Also in the mid to late 1960's there were a lot less foreign cars on the American roads.  The big 3 were still G.M., Ford, and Chrysler.  VW was established and Datsun, and Toyota were in the beginnings of establishing themselves in the American market.  Fiat & Renault were here but both had bad reputations.  The British automotive industry was just a little way from dying.  BMW was still a non entity in the American market.  Big cars and Muscle cars reigned supreme until the first gas crises and OEPC @ 1974 or 75.

I went to work in the harbor in the mid 1970's and the terminal where I worked serviced break bulk ships occasionally, but by 1979(?) the warehouse had been torn down and the area paved over.  The crane that was used for brake bulk had been sold off, and our terminal was strictly containers and ro/ro auto loads and containers on chassis.

Malcom McClean started Sea Land in the late 1940's and was the first to do containerized shipping.  I think by the late 1950's or early 1960's containerization had probably taken over the merchant shipping business.  My father in law was a merchant marine engineering officer during WW2.  He married right after the war, and my wife was born in 1947.  In 1948 he was a first engineer and had completed the papers to become a chief engineer when he decided that he wanted to stay home with his family.  He put the papers in his drawer and quit going to sea.  

In 1968 he was laid off from his job and couldn't find another job, so since he had kept up his membership in the engineers union, he went back to sea.  The last ship he served on was a U.S. lines ship that was break bulk.  The first ship that he went back in in 1968 was the same U.S. Lines ship, but it had been converted to a container ship.  Before he got off the ship in 1948, it took 3-5 days in port to unload and load the ship.  In 1968 it took less than 8 hours to load and unload the ship!  In addition he told us that containerization reduced pilferage by about 90%. 

I think you would need to back date your railroad to the 1950's-early 1960's to avoid containers.  I worked for Sea Land in 1975 or 1976, and while I was working there they got the first double stack cars, and then containerization really took off.  It seemed like everybody went over to double stacks right after that.

Toledo

Look into Toledo, Ohio.  If memory serves there were (are?) some parts plants there and there is a large harbor.  Plus lots of traffic coming down from Detroit. Much of it was served by the Toledo Terminal RR.  Terry Harrison is on this forum and worked for the TT in the '70s.  Maybe he'll chime in.

Scott Chatfield

Double stacks

SP, Sea Land, and American Car & Foundry created the first articulated double stack cars circa 1978, but the idea didn't really take off until the mid '80s.  AC&F had walked away from that business leaving FMC to create the Twin Stack for Sea Land.  About the same time, Thrall Car worked with American Presidents Lines (APL) to rework the Budd Car LoPac (originally intended to haul trailers) into the LoPac 2000.  And the double stack business was off to the races.

Scott Chatfield

Detroit

High Cube boxcars had to ferried across the Detroit River to Windsor, Ontario since they were too tall for the railroad tunnel.  There were auto plants in both Detroit and other places in Canada for destinations for these cars.  Unfortunately this operation ceased about the same time containers became popular.  High cube containers still can't clear the modernized tunnel so they are single stacked.

Robert

Sarnia-Port Huron

Same between Sarnia, ON and Port Huron, MI until CN constructed a brand new replacement tunnel bore in the early 1990s. The brand new tunnel handles all traffic including double stacked containers. The original 1890s Sarnia-Port Huron tunnel is now abandoned and blocked off.

@Nick harbor or river crossing

@Nick,

As Chris says, Port Huron, Mich. to Sarnia, Ont. was very busy river crossing in the 1970s and 80s. Unfortunately no Conrail there, but Grand Truck Western and C&O/.../CSX each operated ferries for auto parts, auto racks and other high and wide loads.

There was a great deal of water traffic moving perpendicular to the rail ferries. Great lakes-based self-unloaders and "salties" via the St. Lawrence Seaway made for a very busy waterway. But no passenger vessels, and a limited number of ships loading or unloading.

What are you seeking in the way of "harbor" activity?

That's a pretty specific request, BUT...

If you're willing to be a little flexible you might consider Milwaukee.  This small city has a ton of character, including still doing some break bulk shipping to this day.  Additionally, there was some auto manufacturing in and around the city. Check out the following area:

mil https://www.google.com/maps/@43.0165269,-87.8962094,3a,75y,70.73h,79.62t/data=!3m6!1e1!3m4!1slczA9dRsSBIJsc7aqEk3Rg!2e0!7i16384!8i8192

-Matt

More specifics and thank you

Thank you all for the input. To answer some of the questions posed above, my principle interests in harbors has to do cement traffic and non-containerized freight, such as steel, high and wide machinery, scrap metal. I am still trying to figure out whether a reasonable harbor can be paired with what will be a multi-siding auto parts facility.