Cerrejón Formation

The Cerrejón Formation is a geological sequence in Colombia featuring substantial coal deposits and remarkably preserved fossils from ancient rainforests. The sedimentary layers span approximately 750 meters of thickness and reveal what tropical ecosystems looked like millions of years ago.

The formation took shape during the Middle to Late Paleocene period, roughly 60 million years ago, when tropical rainforests blanketed the coastal plains of northern Colombia. This era left behind in the sedimentary layers a unique record of vanished ecosystems.

The coal extraction here has shaped the economy of the region, drawing workers from across Colombia and beyond, while the Wayuu people have maintained their presence despite the industrial transformation of their ancestral lands.

Access to the fossil sites is severely restricted and requires special permits since they lie within active mining zones. Visitors should contact authorities or research institutions beforehand to determine if any access is possible.

The layers hold fossils of a giant extinct snake measuring roughly 13 meters long, representing the largest snake species ever discovered. This remarkable creature inhabited the ancient environment and left traces that today tell researchers much about the world of that time.