You can do both in one day, they're close to each other and 2-3 hours at each campus Harvard and MIT is fine.

We visited both of those and the Museum of Science. I would also go check the Peabody museum at Harvard.

There is no entry fee, however if you book a tour they will charge $10-15 per person. I suggest you get the tour as it will give you the historical perspective and an idea what's going on in different department, as otherwise it is very easy to get lost in the block building. I hope this will help

BOS (Logan Airport) is the only Commercial airport near MIT. Suggest a cab if money is not an object. It's easy method with baggage, most direct & "safest" since you can take them any time if day or night. The other reason I suggest a cab is that the MIT area is served by only one MBTA trolley or what is called a "T-stop", and, it's not too close as I recall, Kendall Square. Look up Boston MBTA on Google & study the map. The other option is a bus but that system can be confusing & also not drop you off close to the Endicott house. Again suggest getting a MBTA bus map, study it. It's cost effective & while buses are plentiful from Logan, hauling bags around may be glad you took the cab option and paid a bit more money until you find your way around the MIT campus & Boston.

Hi Sorry for the delay, Catch your flight into Boston Logan Airport, The main Airport for Boston, Quickest way to M.I.T. is to catch a cab, 15 to 20 minutes, or catch the "T" Boston subway,on the silver line then change to the red line which stops at the M.I.T. building. All above courtesy of my sons girlfriend who lives in Boston. Regards Paul Smallwood (U.K.)