Trains

Amtrack: USA
ViaRail Canada

Seat61.com: Train travel across Canada
Seat61.com: Train travel across the United States

More Specific Links: Canada
Agawa Canyon Tour Train
Epic train journey through the Canadian Rockies @ Velvet Escape
13 Reasons to Ditch Airlines for Via Rail

More Specific Links: USA
Verde Canyon Arizona
Cumbres & Toltec Colorado Rockies
West Virginia Mountain Rail Adventures