The Altiplano Cundiboyacense (Spanish pronunciation: [altiˈplano kundiβoʝaˈsense]) is a high plateau located in the Eastern Cordillera of the Colombian Andes covering parts of the departments of Cundinamarca and Boyacá. (Do not confuse with The Altiplano or the Altiplano Nariñense, both further south.) The altiplano corresponds to the ancient territory of the Muisca. The Altiplano Cundiboyacense comprises three distinctive flat regions; the Bogotá savanna, the valleys of Ubaté and Chiquinquirá, and the valleys of Duitama and Sogamoso. The average altitude of the altiplano is about 2,600 metres (8,500 ft) above sea level but ranges from roughly 2,500 metres (8,200 ft) to 4,000 metres (13,000 ft).

Altiplano in Spanish means "high plain" or "high plateau". The second part of the name is a combination of the names of the departments of Cundinamarca and Boyacá.

The limits of the Altiplano are not strictly defined. The high plateau is enclosed by the higher mountains of the Eastern Ranges, with the Sumapaz mountains in the south and Chingaza to the east. The Tenza Valley is located to the east of the Altiplano and the Ocetá Páramo and Chicamocha Canyon are situated to the northeast.

The Altiplano is subdivided into three major valleys, from northeast to southwest:

The average temperature on the Altiplano Cundiboyacense is 14 °C (57 °F), ranging from 0 °C (32 °F) to 24 °C (75 °F). The driest months of the year are from December to March, while rain is more common in April, May, September, October and November. From June to August strong winds are present. Hail is common on the Altiplano.

The Altiplano Cundiboyacense is surrounded by and contains various Andean unique ecosystems; páramos. 60% of all páramos in the world are situated in Colombia. (Specifically, in the department of Boyacá with the most relative area of páramos). Boyacá is the department where 18.3% of the national total area is located. To the south the Sumapaz Páramo (largest in the world) forms a natural boundary of the Altiplano. Chingaza contains páramo vegetation, as does the most beautiful Ocetá Páramo in the northeast. On the Altiplano the microclimate of the surroundings of Lake Iguaque produces a páramo.

Regional geology

The Altiplano Cundiboyacense is formed as part of the uplift of the Eastern Ranges of the Colombian Andes since Neogene times. Hydrothermal activity in fractures of the forming Andean chain left its trace in the form of the many emeralds found in the western and eastern parts of the Altiplano. From the Early Cretaceous until the Eocene, the region of the present-day Altiplano was dominated by a marine environment, as part of the long inland sea of northern South America. In these warm tropical seas a fauna of ichthyosaurs and pliosaurs developed, with important finds (Kronosaurus boyacensis (El Fósil), Muiscasaurus, with four nostrils) in the Paja Formation of Villa de Leyva. During the Late Eocene-Early Oligocene (35-30 Mya) epochs, South America became detached from its longest connected former member of Pangea; Antarctica. The isolation of the South American paleocontinent led to a large biodiversity of New World species.