I spent a week in the Boston area. Beautiful place. I don't know where you're from but have money for tolls. Forth vote for Legal Seafood. A friend recommended it and it was fantastic. If you like to drink or are a fan of Cheers stop by the Bull and Finch Pub. Look for the famous finger and enjoy a drink or two (the interior is nothing like the show).
What's Fun in Boston?
2nd "be prepared for tolls!" comment I've gotten, lol.
Willy, have a great vacation on the Cape. Where do you go?
If you like Italian Food you have to go to the North End of Boston (aka Little Italy). To visit the city, 1-2 days at the most would suffice.
The duck boat takes you all over the city, I beleive you go to the Pru Center for the duck boats.
For history then the Freedom Trail is great for the history buffs.
JFK Library and it was a great tour. You would need to take the subway (red line) outbound to the JFK/UMASS Station.
Boston Public Garden - the duck boats may drive by it.
Baseball Fan - MUST see Fenway.
Have a blast! New England has SO much to offer. Maine is absolutely beautiful.
For places to stay CB is right Woburn is not that far if your have a car. Then I would take a train. The MBTA runs the subway (within the city) and commuter rail (services the suburbs). Cities/towns on the transit system for example are Newton, Brookline, Malden and Braintree. Google maps is an excellent tool to see what type of transit is available to commute into Boston.
Legal Seafood ... definitely
Union Oyster House (for lunch) ... oldest restaurant in Boston
Bull and Finch (the "Cheers" bar) .... but this is no longer a bar. It was converted to apartments the last I heard but check anyway.
Rub a Dub
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