Friends of the Middlesex Fells Reservation recapped this in a Press Release
A blogpost describing the event is available from Friends of the Fells at this link.
Malden News Network provided a short post on Park Serve Day at this link.
Slice of MIT posted a related story: MIT’s Mysterious Observatory Rediscovered
Friends of Fells posted an earlier story, Uncovering the MIT Geodetic Observatory in the Middlesex Fells.
Here's the trail we followed on Saturday, April 29, 2017