Comment by pests

That is a real route though - The Great Loop, although I'm sure tankers aren't taking it.

https://en.wikipedia.org/wiki/Great_Loop

> Assuming a boat ("Looper") begins in Chicago, either take the Chicago River and Chicago Sanitary and Ship Canal, or the Cal-Sag Channel to the Des Plaines River. The waterway passes Joliet and soon becomes the Illinois River. The Illinois River travels west, through several locks, then southward, through Peoria. At Grafton, Illinois, the Illinois River joins the Mississippi River.

Of course you could start in the some Great Lake or the Erie Canal or anywhere else on the east coast.