We travel to Boston a lot, mostly early to mid-October, and stay at Custom House.
We've been 9 times in the last 13 years, and only missed a few because of the pandemic.
We've done many fantastic out-trips, all taking the better part of a day---
to Lexington & Concord (towns and battlefields/historic);
a bus tour to Newport RI to see the many famous mansions (Vanderbilts had two on tour: Breakers and Marble House), and to spend the day walking around Newport;
to Ogunquit ME (great shops and cafes, and the glorious walk along the magnificent spectacular shore, called the Marginal Way);
through the countryside just to see the foliage; stopping at an outdoor produce/apple cider market;
and visiting many other historical places around the Boston area like Waldens Pond,
Sleepy Hollow Cemetery (and the specific area there where many, many famous authors are buried----Author's Ridge).
One time, back in 2019, we rented a car and drove up to Vermont for a few nights and then to New Hampshire for a few more nights....
the foliage was peaking at both places we went (by design as we traveled to NH after VT, and the peak followed us).
We drove the famous Kancamagus Highway, and it was jaw-dropping.
In Boston, there's more to do than you can imagine, and around town the "T" will get you there cheaply and easily.
The Boston Museum of Fine Arts is fantastic. The Harvard campus is beautiful & fascinating. Great architecture. Bookstore alone is great!
Back Bay and the cobbled stone streets of Beacon Hill are a must!
Even the nearby Boston Market is amazing---produce, flowers, etc.
Google "Things to do in and around Boston" and also visit the concierge as soon as you get there.
You may even get a full list of bus day tours (and book one or two)
prior to going so that the special tour you want isn't already booked.
I also
highly recommend doing the city bus tour which leaves just off Atlantic Street in front of the Marriott Long Wharf Hotel & near the Aquarium.
We neglected to do that for at least 6 years, but now we do that at least twice a day when we're there. It looked "touristy" at first but we were truly missing out on a treat.
It's relaxing just to sit and listen, and each tour guide is totally different, and the places you see and the things you learn are NOT in books----absolutely fascinating.
We are returning to our "favorite big city" this upcoming October again, and can't wait.
We love walking to dinner each evening somewhere in the North End ....that's our favorite activity!
We stop in at Modern Pastry (on Hanover Street) way too much ---- it's the best! I also have a great restaurant list for Boston.
BTW, two of our trips in early December, just to experience the Christmas season, and that was so memorable......
Spontaneous musical groups at Faneuil Hall and Quincy Market each day/evening, and the famous huge Christmas Tree is spectacular.
The crowd even joins in on the carols.
Great shopping all over...... and we also attended the Christmas Holiday Pops concert....WOW!
Boston can be cold during Nov/Dec but we just bundled up and went just as in October---it never slowed us down one bit....
even continued our walks to North End for dinner each evening. Some amazing food there..........

P.S. Confession of our secret....Shhhhhhhhh.......We truly love Boston because we can just FEEL the presence of SueDonJ .....