The Cerquilla River begins in the municipality of
Fuentepiñel, then later crosses the south of the municipality of
Fuentesaúco de Fuentidueña, separates
Cozuelos de Fuentidueña from
Olombrada, then enters the municipality of
Perosillo, where it meets with the Cagarroñas stream. After meeting with Cagarroñas, it crosses the urban area of
Frumales and, approaching the last kilometers of its route, enters
Cuéllar through , where it meets with the Mondajos stream and begins to mark the border of the Mar de Pinares. In the La Vega area, next to the Pradillos stream, it borders the area. == References ==