Thank you very much for your replies and also for the useful info.
Actually we considered the ACA TransAmerica Trail but we're afraid it will be to hot in the summer, especially the first half (from east to west).
About the ACA Northern Tier: if possible we would like to add more of Canada. So the route we are currently considering is as follows:
- leaving New York City with the NY State Bike Route 9 to Poughkeepsie, NY (85 miles)
- join the ACA Atlantic Coast to Bar Harbor, ME (542 miles)
- start the ACA Northern Tier and follow it until Ticonderoga, NY (401.5 miles)
(or maybe as an alternative route take the ACA Green Mountains Loop from North Haverhill, NH to Port Kent, NY)
- from there rejoin the NY State Bike Route 9 to Rouses Point on the New York - Quebec border (92 miles)
- cross the border and follow the Route Verte to Montreal, QC (53 miles)
- go to Ottawa, ON on the Trans Canada Trail (300 miles)
- continue to Kingston, ON (160 miles) and join the Waterfront Trail that will take us to the Niagara Falls (260 miles)
- next from Fort Erie, ON along the ACA Lake Erie Connector to Wolf Lake, MI (504.5 miles)
- then follow the ACA North Lakes to Osceola, WI (873 miles)
- rejoin the Northern Tier to Whitefish, MT (1.585 miles)
- follow the ACA Great Parks North to Jasper, AB (616 miles)
- and finish with the Trans Canada Trail again that will take us to Vancouver (720 miles)
If the miles are added up we get something around 6000 miles.
We're ready to take a train or a ferry at some point during the trip, but I still don't know if this is a realistic project as a whole.
What parts of the route could easily be skipped and on the other hand which certainly can't be left out?
Any advice, comments or alternatives are more than welcome ...