Googling around, I saw that there are waterways connecting the St. Lawrence River to Lake Champlain and connecting Champlain to the Hudson river, which leads to New York City and the sea. I wonder if these are used for cruising or for commercial purposes. Are there cruise lines, for example, that offer rides from the St. Lawrence to NYC, or for any part of the trip? Has anyone here done it? Is it a pleasant trip (in the summer, I suspect)? I didn’t even know it was theoretically possible until just now.
Just recreational boating.
Yes there are cruise lines:
https://www.google.com/search?q=champlain+canal+cruises
Perhaps you might watch some Youtube videos to see if you might enjoy a cruise:
https://www.youtube.com/results?search_query=champlain+canal+cruise
I grew up in one of the small towns along the Champlain canal. Back in the 50s and 60s there were oil barges that would go up and down the canal. I don’t remember when they stopped, they just kind of slowed down to a trickle and then were gone. You know, like popping popcorn on the stove.