Island Facts

The sizes of the islands in the park change every hour, as the ocean tides ebb and flow on their shores. All totaled, the park islands change from 1,483 to 3,067 acres during the tidal cycle. Learn how island acreage was measured, considering daily tides.

The names of several islands have also changed over time. How we selected the spelling of island names, and alternate names for some islands, are described in, "What's in a name?"

 
 
 

Contact the Park

Mailing Address:

15 State Street
11th Floor

Boston, MA 02109

Phone:

(617) 223-8666

Contact Us