West of Aibonito the Ruta Panorámica climbs ever higher, eventually skirting the loftiest mountains in the Central Cordillera and slicing through the heart of the Bosque Estatal de Toro Negro (also known as the Reserva Forestal Toro Negro), one of the largest forest reserves on the island. This is the longest continuous stretch of the highway and the most rewarding – an emptier road that traverses the roof of the island along a series of misty ridges draped in thick sierra palm and pine forest. The route affords almost endless vistas of the north and south coast, glittering on the horizon.
The Ruta Panorámica passes through the Toro Negro on PR-143, and all points of interest are accessible off this road. The forest covers around 27 square kilometres and is divided into seven segments: the most convenient for visitors contains the Area Recreativa Doña Juana and peak of the same name, while after a small gap, a larger and higher section incorporates the watershed of the Río Toro Negro, Cerro Maravillas, and Puerto Rico’s tallest mountain, Cerro de Punta. Although the two peaks are easy to climb, it’s frustratingly difficult to explore this potentially more dramatic section without a specialist map and preferably a local guide, as trails are unmarked and hardly ever maintained – casual hikers should stick to the Area Recreativa Doña Juana for a taste of the forest.