Citlaltépetl
Pico de Orizaba, as part of the Sierra Madre Oriental, forms a barrier between the coastal plains of the Gulf of Mexico and the Mexican Plateau. The volcano blocks the moisture from the Gulf of Mexico from saturating central Mexico and influences the climates of both areas. Both the state of Veracruz and Puebla depend on Pico de Orizaba for supplying fresh water. The largest river originating on the volcano is the Jamapa River.