Harbor Islands

Calendar of Events at the Harbor Islands
http://www.bostonharborislands.org/park-calendar
There are many, but just for an example:

 Sunset Clambakes on Spectacle Island 
When: Various times between Jun. 28th - Sep. 14th (See details) 
Where: Spectacle Island
What: Meet your friends, grab your co-workers, and join us in the summertime for a Summer Shack clambake on Spectacle Island

Let's Move Outside When: Various times between Jul. 7th - Jul. 30th (See details) 

Where: Spectacle Island  What: Join us on the fitness program du jour at 11 AM.

During the summer season, park ferries depart frequently from Long Wharf, Boston to Spectacle Island. We suggest arriving at the dock at least 30 minutes prior to departure to allow time for ticketing and boarding. Regular ferry fees apply.

An interisland ferry connecting Georges and Spectacle Islands operates on Fridays-Sundays. Georges Island is accessible from four mainland piers.