N.H. Rev. Stat. § 216-D:2
The commissioner of the department of natural and cultural may acquire by purchase, gift, eminent domain or otherwise such land, including rights of way and easements for the purpose of protecting or enhancing scenic beauty, as he may deem necessary to establish, protect and develop a trail across the state between the Connecticut river and the Maine state line to be known as the Appalachian Trail, and he may provide shelters and other facilities thereon, provided however that the power of eminent domain shall not be utilized to acquire more than 25 acres in any mile of trail. Any department or agency of the state, or any political subdivision, district or authority may transfer to the department land or rights in land for said purposes on such terms and conditions as may be agreed upon, or may enter into an agreement with the commissioner providing for the establishment and protection of said trail. The Appalachian Trail shall be held, developed and administered under this chapter primarily as a footpath and the natural scenic beauty thereof shall be preserved insofar as is practicable, provided however that the commissioner may permit other uses of the trail and land acquired hereunder, by the owner of adjoining land or others, in such a manner and at such seasons as will not substantially interfere with the primary use of the trail. Nothing in this section shall be construed to limit the right of the public to pass over existing public roads which may be or become part of the trail, nor prevent the department from performing such work as is necessary for the purpose of forest fire prevention and control, insect pest and disease control and the removal of damage caused by natural disaster.
RSA 216-D:2
1971, 279:1, eff. Aug. 22, 1971. 2017, 156:14, I, eff. July 1, 2017.