David sent this in from The Granite Glider Guiders a southern New Hampshire area club.
Deer Island is just minutes from downtown Boston and offers both east and west facing slopes. The property is part of the Boston Harbor Islands National Recreation Area. Public areas are open dawn to dusk every day. Using the address 175 Tafts Ave., Winthrop, MA 02152 will get you close. The parking area is at the end of Tafts Ave.
There are several paved foot paths but the direct route to the launch areas is a well worn, uphill dirt path from the parking lot. In addition to seagulls and other soaring birds, the site is often frequented by members of the Charles River R/C Club. One of their more video inclined members has posted a short clip of a soaring session at Deer Island during November, 2007.
When the winds are westerly you get a great view of downtown Boston and Logan Airport.
At the southern end of Deer Island is a $4 billion technological marvel, a wastewater treatment plant that has ended centuries of sewage discharges into Boston Harbor. For more information about the site, check the Massachusetts Water Resource Authority website.