San Juan ( Spanish Río San Juan ) is a river in Argentina of the province of the same name . On the river is the city of San Juan . The river originates in the Patagonian Andes , from the confluence of the Patos and Castaño Viejo rivers at an altitude of 1,330 meters above sea level. The confluence of the rivers is located east of the Chilean - Argentine border. At the confluence of the Mendoza River, at an altitude of 497 meters above sea level in the lagoon of Lagunas de Guanacce, the Desaguadero River originates.
| San juan | |
|---|---|
| isp. Rio san juan | |
 | |
| Characteristic | |
| Watercourse | |
| Source | confluence of the rivers: Patos and Castaño Viejo |
| • Height | 1330 m |
| • Coordinates | |
| Mouth | Desaguadero |
| • Location | Lagunas de guanacache |
| • Height | 497 m |
| • Coordinates | |
| Location | |
| Water system | Desaguadero → Rio Colorado → Atlantic Ocean |
| A country |
|
| Region | San juan |
 - source  - mouth | |
