Main Route/Main Route concurrencies

[Roadgeekteen]

Did anyone mention I-20 & 59 through MS and AL?

Also the infamous US 1 & 9 in NJ that NJDOT gave it single shield like it is one route rather than two separate US routes as it really.  It is a main route not by long distance as I-95 and the NJ Turnpike take that title, but regionally the one and nine is important as it serves many cities like Rahway, Linden, Elizabeth, Newark, and Jersey City and used heavily by trucks delivering along the Chemical Coast and all the industrial plants along the Arthur Kill.

How are you defining "main route" to include I-59?

It is a 2di, which can be considered as main.