Mystic Seaport in New London CT.
The Newport (RI) mansions. You can park at Horseneck Beach for a day and night (no hookups) and you're within a half hour of Newport.
While on the Cape, take a side trip to Plymouth, America's Home Town and the location of the most disappointing tourist attraction (The Rock).
Also while on the Cape, don't miss Provincetown. October is the perfect time of the year to go there.
Your best chance of seeing foliage would be in southern CT.
Jerry & Jeanne
1996 Safari Sahara 3530 - 'White Tiger'
CAT 3126/Allison 6 speed/Magnum Chassis
2014 Equinox AWD / Blue Ox