Puerto Rico Highway 172

Puerto Rico Highway 172 is a main highway that connects Caguas, Puerto Rico at PR-1 to downtown Cidra, Puerto Rico and continues its way to its end at Puerto Rico Highway 156 in Comerio, Puerto Rico. It is a two-lane per direction road from Caguas to its border point to Cidra and rural all the way to Comerio.

Dangerous Highway

Puerto Rico Highway 172 is perhaps the most dangerous highway in the island in terms of its design. In its way to Cidra, it has about 4 kilometers going uphill. One side of the road is extremely close to the blasted mountain ("See Blasting"), meaning that landslides would fall in the right lane of the direction close to it; the other side is near a precipice, with barriers that are not safe. The two directions are not divided, and cars can easily collide front-to-front. Several people have died in this highway, including cars which have been collided by heavy-weight trucks that come so fast downhill their brakes malfunction or don't have to time to stop. The most recent death occurred July 9, 2008. Some local people name this segment of PR-172 "Carretera de la Muerte" ("Death Highway"). Only one emergency ramp has been built to provide safety in the down part of the mountain.

Rural Road in Cidra

Similar to other highways in Puerto Rico which become rural after entering another town from the town of origin, PR-172 becomes rural and enters downtown Cidra before continuing to its end at Puerto Rico Highway 156 in Comerío. It is mainly flat, and there are no precipices found in the rest of the highway.

From Cidra to Comerio

The highway leaves the area of downtown Cidra and becomes a narrow rural road to Comerio, where it ends at PR-156.