Maine - NO DESIGNATED CROSS STATE ROUTES 
Route Description
US-1 From northern border to New Hampshire
ME-161 From northern border to Fort Fairfield
US-2 from western border to eastern terminus
ME-11 From Knowles Corner to Sherman Mills
ME-191 From Calais to US-1
ME-182 Entire length
ME-116 From Howland to Bangor
ME-100 From Waterville to Augusta
many short segements of state highways in loops
ME-9 Bangor to eastern border
www.exploremaine.org/bike
Adventure Cycling Northern Tier and Atlantic Coast routes (not on map)
Maryland - NO DESIGNATED CROSS STATE ROUTES 
State bycycle suitability map shows only shoulder width and contains
no designated routes.  The extensive network of roads would allow definition of
several cross-state routes.  State bike/ped coordinator is proposing the routes on the map
but they are not official yet.  One of the routes is the C&O Canal towpath, which is not 
really suitable for road bikes.
Adventure Cycling Atlantic Coast and Tidewater Potomac routes (not on map)
Massachusetts - plan in development for 3 N-S and two E-W routes, but no current routes
From the Western MA Bike Routes study of 1993
North and South Berkshire routes on mostly secondary roads
Connecticut Valley route on mostly secondary roads
Largely bike path route (long term) from Northampton to Boston
US-20 west to east (follows I-90 corridor)
MA-9 west to east (follows I-90 corridor)
MA-2 follow the MA-2 corridor (much is freeway)
Cape Cod to Boston to Cape Ann bikeway
MA-12, 13, 31 Providence RI to Worcester and north to NH
State bicycle suitability map shows recommended and secondary bike routes.
The extensive network of roads would allow definition of
several cross-state routes.
Adventure Cycling Atlantic Coast route (not on map)
Michigan- NO DESIGNATED CROSS STATE ROUTES
DALMAC
PALM
ODRAM
Michigan has an extensive network of state and county roads and their cycling
suitability map has categorized them in detail.
The combination of these roads would allow the development of routes 
connecting virtually any two destinations, including connections with routes from
other states.  Only major metropolitan regions present any barrier.  Lansing to Mackinac ride (mostly secondary roads)
Adventure Cycling Lake Erie Connector and North Lakes routes (not on map) Pedal Across Lower Michigan (mostly secondary roads)
One Day Ride Across Michigan (mostly secondary roads)
Minnesota
Draft plan per the attached map.  Red (burgandy) segements are on state/US highway
MN plan includes Mississippi River Trail segment
Green segments are existing or proposed off-road trails
Adventure Cycling Northern Tier route (not on map)
Mississippi
Natchez Trace Parkway
Mississippi River Trail
BAM (Bike Across Mississippi) roughly follows I-20, much it on US-80
Adventure Cycling Southern Tier and Great Rivers South routes (not on map)