Riolos
| Riolos Ρίολος | |
|---|---|
| Coordinates: 38°01′N 21°28′E / 38.017°N 21.467°E | |
| Country | Greece | 
| Administrative region | West Greece | 
| Regional unit | Achaea | 
| Municipality | West Achaea | 
| Municipal unit | Larissos | 
| Elevation | 100 m (300 ft) | 
| Population  (2021) | |
|  • Community | 494 | 
| Time zone | UTC+2 (EET) | 
| • Summer (DST) | UTC+3 (EEST) | 
| Postal code | 270 52 | 
| Area code(s) | 26930 | 
Riolos (Greek: Ρίολος) is a village and a community in the municipal unit of Larissos, Achaea, Greece. It is located on the northwestern edge of the Movri hills, 4 km north of Mataragka, 3 km southwest of Krinos, 6 km southeast of Lappas and 32 km southwest of Patras. The community includes the small village Mazaiika. The river Larissos flows southwest of the village. During the Greek War of Independence a battle took place in Riolos in which the Greeks, led by Thallis Theodoridis the Elder, were victorious.