Thank you all for you suggestions.

Will check out the flights into Toronto.

Still not sure of renting a car and driving to the falls, but I really feel better about it having your help. Staying near the fall one night might be nice as well. Keeping the car in Toronto seems viable, but I am getting concern beyond. We also use hop-on and off, but either way we pay while spending hours in a zoo or a museum.

Would like to hear more about the train, between the Cities. WE are 71. We will have 2 roller-bags, a garment bag and likely 2 small back packs. How does one handle luggage on the train (physically on and off). My wife is not much of a lifter. Does the train leave from the Airport in Toronto? Does in go into the cities? or a central station. Especially wonder about Quebec City as to AP.

Unlike the road trip presented, we will be Toronto, Ottawa, Montreal and then Quebec City. We neither read nor speak any French (except for modest courtesy phases and words). I am comfortable driving, but do need to avoid being a hazard to others, checking out signs. this is the only reason I ask about the trains, above.

We will be in Denmark in May for 3 full days and will not have a car. We will get the Copenhagen card and use the train and metro to get around. We plan to do similar things there as we speak of here. We are posting at the AP Hilton, but only because we have a very early flight. If our flight was later we would likely have planned to stay in town. We do not have to deal with our luggage and the train, as we are exiting a cruise, taking a tour bus that eventually drops us off at the Hilton Airport where we will check in.