Another one would be DK the old routing of highway 57 a good bet that stand for Door and Kewaunee Counties.
There is also the famous DL in Sauk County which of course stands for Devils Lake.
Rock County has a BT which I assume is an abbreviation for Beloit.
Outagamie County has a CA which you could argue is an abbreviation for College Ave the name of the road or county airport since that is where it goes to.
Brown and Outagamie County 'CE' is the eastward extension of College Ave from WI 441 in Appleton to WI 57 in Brown County (unincorporated Hollandtown). The part that is closer to Appleton is built to a fairly high standard and it is what I would consider to be a 'natural' future reroute for US 10 eastward from Appleton towards Manitowoc.
Also, running north-south past the ATW airport is Outagamie and Winnebago County 'CB'.
Mike
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Topic: Symbolic county road letter designations in Wisconsin (Read 9335 times)