We have 19 days in July, flying in and out of JFK (no changes possible) 2 July to 21 July this year. We want to spend at least 6 Days in NYC and are booked to see the Yankees on 4 July. We plan to leave NYC on 9 July.
What we'd like to do is 3 Days in DC, 1-2 Days Niagara Falls, 2 Days in Boston, and 5 Days driving possible options Maine/Vermont/New York State/Rhode Island.
What I'd be so happy with is any suggestions here on the best way to do this kind of thing. My partner thinks flying between NYC, DC, BUF and BOS, but I'm concerned about wasted time in checking in eclipsing the extra time a train would take etc.
Also any thoughts on the plan in general, it sounds okay to me, and when I look at what we want to see, i think we can do it, but you people are so knowledgeable I'm sure you've got a better idea? Thank you very much, Melissa

Melissa, you may want to reconsider Niagara Falls. While it is an amazing natural wonder, that area deserves only a day or less to see the falls, Buffalo could be one of the most depressed and depressing cities in the United States, and that general area is pretty much out of your way considering the rest of your itinerary.

The rest is certainly doable. I'd suggest taking the train from New York to DC; Amtrak runs a (relatively) high-speed service called Acela. You won't want or need a car in DC (Boston, either), and you're right about the time equaling that of flying. If the early history of this country is of interest to you, then you may want to think about stopping in Philadelphia, perhaps overnight.

You'd be best off flying to Boston from DC, then driving through New England and maybe returning to Boston, whence you can take the Acela back to New York. Driving from NYC either to DC or Boston is via very heavily-traveled routes, often with significant traffic delays; thus, I suggest the train for those legs.

If budget is an issue, there is inexpensive express bus service from NYC to Boston, Philly and DC. Of course you'd be subject to the same traffic delays as if you were driving.

I'd fly. NYC to BUF on the train takes almost 8 hours. BUF-BOS or BUF-WAS is 11 or 12 hours.

Fly NYC-BUF-WAS-BOS then drive then train BOS-NYC. Something like that.

Thanks, I think we'll train to DC, then, as we really do want to include Niagara Falls, but we are now thiniking to fly to Buffalo from DC in the morning, stay overnight at the falls, perhaps 'Sheraton on the Falls'??? We'd love to have a view from our room, then leave after lunch the next day for Boston where we would hire a car.
Does this sound doable?
I know it'll be a whistlestop tour if we want to see anything of Maine, Vermont, New Hampshire, Rhode Island, but if I only have three and a half days from Boston and returning to Boston (for the train back to NYC)how should i prioritise.
We like architecture and natural scenery and thing unique to a place, are not really museum, gallery or tourist attraction / trap types (I hope that doesn't cause offence).
Any opinions of how to structure the three and half days would be really appreciated. Thank you so Much, Melissa

You are really short-changing Boston by spending only 2 days there. You can see a decent amount of ME/NH in 3 days... not sure what you have in mind when you put in Rhode Island?

For New England, you can head up to Maine along the coast on for a day and a half, then head inland into NH for the mountains for the other day and a half. There's a lot of different things to see in New England, so it will be helpful if you can tell us if you want to see :

Rocky coast (ie, coast of Maine)
Sandy beaches
Mountains and hiking...

Unless you will be satisfied with only a quick look at Niagara Falls, I think you'll be sorry to have scheduled only one day there. You definitely want to stay on the Canadian side - due the configuration of the Falls, views are far superior on that side. Sheraton on the Falls is an excellent choice, both for views and location (it's right across from Maid of the Mist).

Five days is not much time for Maine/Vermont/New York State/Rhode Island. Best be would be to decide whether you want to head for the mountains or enjoy the seaside areas. Unless you specific destinations in mind for Rhode Island, why go there? Or, New York State.

Note that DC will likely be extremely hot and humid during your visit, which can really slow you down. And, seven days in NYC, which will also likely be very hot and humid, is probably a few days too long, unless you have plans for those days you can't cancel.

If you do Niagara Falls at all you really need to fly.

It makes sense to do

NYC
Train to DC
Fly to Niagara Falls (really Buffalo)
Fly to Boston (train would take a couple of days)
Stay in Boston
Rent a car when you leave Boston to see New England and return in NYC

Also be aware that most of the good stuff in Niagara Falls is on the Canadian side - so you need to alow time for border crossings - and be sure your passport and visa (if you need them) allow for re-entry into the US.

Flying is really the only way to see the Falls - since it's a full day's drive from NYC or Boston and further from DC.
Train service outside the NE corridor (from Boston to NYC to DC) is extremely limited. Many routes have 1 or 2 trains per day and trains don't go a lot of places at all. To get from Niagara Falls to Boston by train you have to backtrack to NYC and change lines to train to Boston - 14 hours at least).

The coast of Maine (an easy drive from Boston) is not only naturally spectacular, but also has wonderful small towns to poke around in (both beach towns, and quaint towns on the beach, but not with the beach-town vibe).

Thank you all so much for your helpful suggestions.
nytraveler, we think we'll do it as you suggested except we've heard that one way hire car drop off fees would make pick up in Boston and Drop Off in New York very expensive. Is this true?
How would three and a half days be to head up the coast of Maine, spend some time in New Hampshire, the Vermont and Back down to Boston, in time to catch a late afternoon, evening train to NYC.
I would love some ideas of places to see. I have a list a mile long, but will need to prioritise. We really love natural scenery and coastal landscapes along with unique architecture.
Thanks again for all your help, Melissa