Boston, I have been there twice with my son, once as a port form Anthem and the other on an overnight 6th grade school field trip.
The port day was better. We went to see the USS Constitution https://www.nps.gov/bost/learn/historyculture/ussconst.htm Caleb loves this type of historic thing. It was an adventure in public transportation. We took a taxi there, arrived at opening, went to the museum and into the ships at the site. It's on the OTHER side of town.. We water taxi'd back to the Boston Aquarium area, met an old friend who lives in Boston, and went to the children's museum with her 3 year old. It was a good day; August, not to hot, not too cold.
On the school field trip, on our own we went to the Aquarium, had lunch at the Boston Sail Loft (it was very good), walked the Freedom Trail, toured Paul Revere's house, went to Quincy Market, then ate as a group at the Hard Rock Cafe. Day 2, we went as a group to the Museum of Science, ate lunch there (awful lunch.. neat museum), then went on a Duck Boat Tour https://bostonducktours.com/ It was a very different perspective of Boston!
Halifax: We opted to take a taxi ($5.00 CAD) up to the Citadel, toured that, then wandered downhill to the Boardwalk, and went to Tim Horton's!! (It's better in Canada than the US), enjoyed a snack of coffee and donuts and cocoa ( AND free WIFI ), then wandered back to the ship along the boardwalk. We stopped at the Maritime Museum (more historic boats for Caleb)..
St. John: We left the boys in Adventure Ocean.... My husband and I walked from the pier to the left, along the waterfront all the way to the reversing rapids and back. It was concrete or pavement the entire way. It was a nice walk, and we watched harbor seals, which I hear is an uncommon sight (we were lucky).
Ahh.. Bar Harbor. Acadia National Park is NOT flat. We rented bikes from Acadia Bike Rentals. We took the bike shuttle into the park, then proceeded to ride around a lake. Eagle Lake? (not sure)My youngest's bike would not shift gears for him, I had to fiddle with it to get it into the lowest gear, and we left it in that gear. So I have a lovely family photo of the 4 of us BEFORE the bike ride. But not one AFTER. There were tears. There was frustration. We walked. fter all this, I would love to do it again, with my own bike and breakdown gear. Alone.
Then we received a full refund for Josh's bike rental. MORAL: if you ever rent a bike, put it on the stand in the shop, and try all gears and the brakes. We ate at the gloriously fun tourist trap Route 66 Restaurant, then entire family was back into happy cruising mode. Portland: We just walked around the port and shopped. It seems there is a port on each trip where we are wiped out and need a day "off". Portland is a port town, I do want to give it a second chance. Perhaps whale watching?
Have a great New England trip. It is by far, my favorite cruise ever. We went in late August, the temperatures were mild, the seas calm. That is remarkable out of Bayonne.