[JohnRPollard]

The Boston Harbor Islands should be an easy daysail/overnight destination. You can go to the southern end and visit the Hingham, Nantasket area as well, some good seafood restaurants there.

I would think you could reach a number of places on the South Shore in one 6-8 hour daysail. Cohasset harbour is pretty tight, but there is a nice low-tide sand bar out near the mouth for a quick stopover and good swimming. Scituate harbour is quite a bit larger, very nice with good provisioning, restaurants, ice cream shops, movie theaters, etc., all easy strolling distance.

Just a mile or so south of the Scituate harbour bell buoy is the shared mouth of the North and South Rivers ("New Inlet" on the charts, between Third and Fourth Cliff), where there is a massive sand spit. Great beaches at low tide, and even at high tide duned portions remain above water. There is good anchorage protection up the North River portion in a hole beyond the dunes. HOWEVER, DO NOT attempt this inlet in anything but completely benign conditions, preferably even then at slack tide. Also, it is powerboat mayhem on sunny summer weekends -- to be avoided. At other times it is bucolic.

It would be a longer stretch down to Duxbury Bay/Plymouth Harbour, you'd probably want to stopover somewhere enroute unless you had a fair wind and plenty of daylight. Arrive with a rising tide or fight a nasty current on your way in. Once there, Plymouth is nice for a visit, and there are some quieter anchorages further up into Duxbury Bay past Clark's Island. It would be good to have a dinghy for getting ashore at the Gurnet or Saquish.

P-Town is also within striking distance, but requires more planning and a decent weather window.