Bolaños River (bo-LAHN-yos), c.80 mi/129 km long, Jalisco state, W Mexico; formed by Mezquitic and Colotlán rivers 40 mi/64 km SW of Colotlán near Zacatecas border. Flows NNE-SSW, past Bolaños and San Martín de Bolaños, to Santiago R. Merges with Lerma-Santiago S of Sierra Bolaños.