Taking in a Red Sox game at Fenway Park.
Running, walking, or biking along the Charles River or, better yet, sailing on it with Community Boating.
Seeing magnificent whales and their young close-up on a whale-watch boat tour.
Exploring the quiet, awe-inspiring trails and shorelines of the Boston Harbor Islands.
Strolling through the parks and gardens of the Emerald Necklace (including the Boston Common and Public Garden).