The Eastern Mountains (Montañas del Oriente) are in the east of the state, formed by various parallel mountain chains mostly made of limestone and sandstone. Its altitude varies from . This area receives moisture from the Gulf of Mexico with abundant rainfall and exuberant vegetation, which creates the Lacandon Jungle, one of the most important rainforests in Mexico. The Northern Mountains (Montañas del Norte) are in the north of the state. They separate the flatlands of the Gulf Coast Plains from the Central Depression. Its rock is mostly limestone. These mountains also receive large amounts of rainfall with moisture from the Gulf of Mexico giving it a mostly hot and humid climate with rains year round. In the highest elevations around , temperatures are somewhat cooler and do experience a winter. The terrain is rugged with small valleys whose natural vegetation is high altitude rainforest.