| State: | PR |
| Type: | PR |
| Route: | 633 |
| Length Km: | 4.3 |
| Established: | 1953 |
| Direction A: | West |
| Terminus A: | in Hato Viejo |
| Direction B: | East |
| Terminus B: | in Barahona |
| Municipalities: | Ciales, Morovis |
| Previous Type: | Ter |
| Previous Route: | 591 |
| Next Type: | Ter |
| Next Route: | 647 |
Puerto Rico Highway 633 (PR-633) is an east–west rural road located between the municipalities of Ciales and Morovis in Puerto Rico. With a length of 4.3km (02.7miles), it begins at its intersection with PR-149 in Hato Viejo barrio and ends at its junction with PR-155 in Barahona.
Due to its rural characteristics, PR-633 consists of one lane per direction for its entire length. In Ciales, it extends from PR-149 intersection to the Morovis municipal limit, making its way through Hato Viejo barrio. In Morovis, PR-633 extends to the east within Barahona barrio from the Ciales municipal limit until its eastern terminus at PR-155 junction. In both municipalities, this highway serves as the main access to several neighborhoods and sectors between PR-149 and PR-155.
The entire length of PR-633 is part of the western section of the old Road 20, a highway that led from Naranjito to Ciales through Corozal and Morovis until the 1953 Puerto Rico highway renumbering, a process implemented by the Puerto Rico Department of Transportation and Public Works (Spanish; Castilian: Departamento de Transportación y Obras Públicas) that increased the insular highway network to connect existing routes with different locations around Puerto Rico. Route 20 was divided into two segments: the first one, from Naranjito to Corozal, and the second one, from Corozal to Ciales. The first section corresponds to the current PR-164 from PR-167 (old Road No. 9) to PR-159 (former Road No. 10), while the second one went to Morovis through PR-159, beginning at its junction with PR-568 (old Road No. 10) in western Corozal to continue to Ciales through PR-155, PR-633 and PR-6633 until its end at PR-6685 (former Road No. 11).
| State: | PR |
| Type: | Sec |
| Route: | 6633 |
| Length Km: | 0.22 |
| Location: | Ciales |
Puerto Rico Highway 6633 (PR-6633) is a spur route located in Ciales. With a length of 0.22km (00.14miles), it extends from PR-6685 to PR-149, near to the western terminus of PR-633.