53 Pa. Stat. § 16502
There shall be laid out and constructed a road of easy and practicable grades, extending from the intersection of the northerly line of the park by Belmont avenue on the westerly side of the river Schuylkill, to the head of Robert's hollow, and thence along said hollow and the river Schuylkill to the foot of City avenue, laid out with the ground contiguous thereto for ornamentation, of such width and so constructed as the commissioners of Fairmount park, appointed under authority of the act of the general assembly of the commonwealth, may determine. And such road and its contiguous ground are hereby declared to be a part of the aforesaid park; and the said park commissioners are hereby authorized and required to ascertain, by a proper survey, the limits thereof, which survey they shall file in the survey department of the city of Philadelphia.
53 P.S. § 16502