| State: | PR |
| Type: | PR |
| Route: | 20 |
| Alternate Name: | Spanish; Castilian: Expreso Rafael Martínez Nadal |
| Maint: | Metropistas |
| Length Km: | 9.5 |
| Direction A: | South |
| Terminus A: | in Río |
| Junction: |
|
| Direction B: | North |
| Terminus B: | in Pueblo Viejo |
| Municipalities: | Guaynabo, San Juan |
| Previous Type: | Ter |
| Previous Route: | 19 |
| Next Type: | Urban |
| Next Route: | 21 |
Puerto Rico Highway 20 (PR-20) or Spanish; Castilian: Expreso Rafael Martínez Nadal is a short tollway located between the municipalities of Guaynabo and San Juan in Puerto Rico.[1] With a length of 9.5km (05.9miles), it begins at PR-2 interchange in Pueblo Viejo barrio and ends at PR-1 junction in Río barrio.
It used to be divided highway with traffic signals, which even turned into a rural road near its south end, but due to the traffic congestion in parallel freeway PR-18, and also in PR-1 and PR-52, it had to be converted and is now 9.5 kilometers long.[2] It has few exits; the first being to PR-169, a road to the rural area of Guaynabo and part of Aguas Buenas; PR-199 which connects it to PR-1 and PR-52; PR-177 which serves Bayamón and Cupey, and PR-17 (Spanish; Castilian: Avenida Jesús T. Piñero). It begins in the Muda sector of PR-1 and ends near San Patricio in Caparra, Guaynabo, at PR-2. It is tolled going north from PR-1, but not in the other direction.