It’s hard to tell how old a foundation in the woods has been abandoned. But some make it easy to distinguish between “old” and “really old.” Take the J.A. Gallopp House ruins on Coop Road. The foundation has mostly filled in with just a bump in the middle where the chimney once stood. On the north side is a filled-in well. But the most telling sign are the multiple large trees growing out of the foundation. For anything to even start growing, the entire structure needed to be gone and the foundation needed to be filled in. The fact that multiple trees could root and grow to a decent size shows the site has been abandoned for many decades.
Nearby to the house foundation across a trail is a smaller foundation, likely that of a barn or shed.
The house is not listed on an 1874 map of Glastonbury but it is on a 1855 map of Glastonbury. The latter lists it under the name JA Gallopp.
Lost Glastonbury 