There is potential for a claim of adverse possession here, so you need to resolve it and investigate here.
§812. Acquisition of rights-of-way and easements by adverse possession; notice to prevent
No person, class of persons or the public shall acquire a right-of-way or other easement through, in, upon or over the land of another by the adverse use and enjoyment thereof, unless it is continued uninterruptedly for 20 years. If a person apprehends that a right-of-way or other easement in or over his land may be acquired by custom, use or otherwise by any person, class of persons or the public, he may give public notice of his intention to prevent the acquisition of such easement by causing a copy of such notice to be posted in some conspicuous place upon the premises for 6 successive days, or in the case of land in the unorganized territory, by causing a copy of such notice to be recorded in the registry of deeds for the county where his land lies, and such posting or recording shall prevent the acquiring of such easement by use for any length of time thereafter; or he may prevent a particular person or persons from acquiring such easement by causing an attested copy of such notice to be served by an officer qualified to serve civil process upon him or them in hand or by leaving it at his or their dwelling house, or, if the person to whom such notice is to be given is not in the State such copy may be left with the tenant or occupant of the estate, if any. If there is no such tenant or occupant, a copy of such notice shall be posted for 6 successive days in some conspicuous place upon such estate. Such notice from the agent, guardian or conservator of the owner of land shall have the same effect as a notice from the owner himself. A certificate by an officer qualified to serve civil process that such copy has been served or posted by him as provided, if made upon original notice and recorded with it, within 3 months after the service or posting in the registry of deeds for the county or district in which the land lies, shall be conclusive evidence of such service or posting. [1971, c. 450, §1 (AMD).]