| Pas | |
| Subdivision Type1: | Country |
| Subdivision Name1: | Spain |
| Subdivision Type2: | State |
| Subdivision Name2: | Cantabria |
| Subdivision Type3: | Region |
| Subdivision Name3: | Pas valley, Santander bay |
| Length: | 57km (35miles) |
| Discharge1 Location: | mouth |
| Discharge1 Avg: | 18.1m3/s |
| Source1 Location: | Castro Valnera |
| Source1 Elevation: | 1200m (3,900feet) |
| Mouth: | Ría de Mogro |
| Mouth Location: | Santander bay, Bay of Biscay |
| Mouth Elevation: | 0m (00feet) |
| Basin Size: | 649km2 |
| Tributaries Left: | Yera, Viaña, Magdalena, Jaral, Barcelada |
| Tributaries Right: | Pandillo, Pisueña |
The Pas River is located in the region of Cantabria in the northern part of Spain.[1] The river flows through the autonomous community of Cantabria and empties into the Cantabric Sea.