I think this is the complete list. This is for signed 3-di routes.
Olympia,WA
Salem, OR
Sacramento, CA
Phoenix, AZ
Santa Fe, NM
Bismarck, ND
Pierre, SD
Lincoln, NE
Austin, TX
Jefferson City, MO
Madison, WI
Springfield, IL
Montgomery, AL
Charleston, WV
Dover, DE
Montpelier, VT
I feel I’m missing some…