Charcas is a municipality located in the Altiplano Zone of the state of San Luis Potosí in Mexico, whose municipal seat bears the same name. The town of Charcas is located 191 km north of the city of San Luis Potosí. According to the 2010 Population and Housing Census prepared by the National Institute of Statistics and Geography, the municipality of Charcas had until that year a population of 21,138 inhabitants, while the city had a population of 12,748 inhabitants, which represents 60.31% of the municipal population, bordered on the north by the municipalities of Santo Domingo and Catorce. To the east with the municipalities of Catorce and Villa de Guadalupe. To the south with the municipalities of Venado and Salinas.
To the west with the municipalities of Salinas and Santo Domingo. This population is communicated by the federal highway 63, that goes from San Luis Potosí to Matehuala, and by the route of the National Railroad that goes to Nuevo Laredo.