The Amacuzac River is one of the most important tributaries of the Balsas River. It originates on the slopes of the Nevado de Toluca, in the State of Mexico, where it is known as Texcatitlán River. The Amacuzac River runs through the valley of Almoloya de Alquisiras, after 75 km it reaches the Sierra de Cacahuamilpa, then it disappears at the foot of Jumil Hill and turns into an underground river.