This town with a population of 2,216 as of 2010 is home to a fortification at the mouth of what river?
Phippsburg, Maine:  A tourist destination, Phippsburg is home to Bates-Morse Mountain Conservation Area, Fort Popham State Historic Site; it is also home to Fort Baldwin which overlooks Fort Popham, and Popham Beach State Park, as well as Pond Island National Wildlife Refuge.
i don't know