Rio Tula is a river in Hidalgo State in central Mexico emptying into the Amajac River. It runs through the city of Tula de Allende and begins as a drainage channel for the Valley of Mexico containing Mexico City.
The river is significally contaminated with both organic and inorganic substances.
Coordinates: 20°35′02″N 99°19′43″W / 20.58389°N 99.32861°W