Puerto Rico Highway 139

Puerto Rico Highway 139 (PR-139) is a two-way secondary highway in the municipality of Ponce in Puerto Rico. With a length of 25.2 km, it extends from the interchange of PR-10 and PR-14 located in Barrio Machuelo Arriba to the junction with PR-143 on the Ponce–Jayuya municipal limit.

Route description
The road runs south to north through Barrio Machuelo Arriba, where serves as the main access to few communities and neighborhood developments before leaving the city of Ponce to the mountains. Then, the road makes its way though the rural area, mostly alongside Río Cerrillos in barrio Maragüez, bordering the western bank of Lake Cerrillos until it reaches upstream of the reservoir, where it crosses the river for make its way along its eastern bank. Farther north, PR-139 climbs the mountains of the Cordillera Central through Barrio Anón until its terminus at the Ruta Panorámica.

Communities served
As the road is traveled in a northbound fashion, it serves barrios Machuelo Arriba, Maragüez, and Anón. In Machuelo Arriba, PR-139 meets with PR-505, PR-139R, PR-5139, and the Río Bayagán; in Maragüez, it crosses through Cerrillos State Forest, and in Anón, it meets with Río Prieto and Río Blanco, two tributaries of the Río Cerrillos.

History
The entire length of PR-139 is part of the old Road No. 51, a highway that led from Ponce to Jayuya until the 1953 Puerto Rico highway renumbering, a process implemented by the Puerto Rico Department of Transportation and Public Works (Departamento de Transportación y Obras Públicas) that increased the insular highway network to connect existing routes with different locations around Puerto Rico. Route 51 extended from PR-14 (old Road No. 1) between barrios Machuelo Abajo and Machuelo Arriba to the intersection of PR-143 with PR-140 (former Road No. 15) on the Ponce–Jayuya–Utuado municipal tripoint. Its original way currently corresponds to PR-139 and PR-143, the latter from PR-139 in the east to PR-140 in the west. PR-139R also belongs to an original segment of the old Road No. 51. The other part of the highway disappeared after the creation of Cerrillos Dam.

Related routes
Currently, Puerto Rico Highway 139 has two branches along its route in Ponce.

Puerto Rico Highway 139R
Puerto Rico Highway 139R (Carretera Ramal 139, abbreviated Ramal PR-139 or PR-139R) is a spur route or ramal from its parent route PR-139 between barrios Machuelo Arriba and Maragüez. With a length of 2.9 km, is the main (and only) access to Cerrillos Dam and Luis A. "Wito" Morales Park.

Puerto Rico Highway 5139
Puerto Rico Highway 5139 (PR-5139) is a north–south connector located between PR-14 and PR-139. With a length of 2.8 km, this road runs through barrios Cerrillos and Machuelo Arriba, crossing the Río Cerrillos near Cerrillos Dam.