The Guanajuato's River (Spanish: Rio Guanajuato) is a tributary of the Lerma River in the central near region of Mexico called the Bajio (Lowlands). The river begins in the silver-rich Guanajuato mountains near the state capital of Guanajuato City. The river is fed by the Guanajuato river basinca (in Spanish: cuenca) (a sub-basin to the much larger Lerma–Chapala Basin) and has an area of 3,320 km², which makes up approximately 10.32% of the total area of the state.[1][2] There are approximately 900,000 people living in the Guanajuato River basin area, in the municipalities of Guanajuato, Irapuato, Romita, San Francisco del Rincon, Manuel Doblado and Pueblo Nuevo.[3]