Titanoboa cerrejonensis lived about 60 million years ago, shortly after the dinosaurs went extinct. Fossils indicate it reached 12.8–14.3 meters (42–47 ft) in length and weighed around 1.1 tonnes (≈2,425 lbs), making it the largest snake known at the time of its discovery. Recent finds of Vasuki indicus may rival its length, but Titanoboa remains unmatched in mass.

It lived in a hot, swampy tropical ecosystem at the Cerrejón, alongside giant turtles and crocodilians. Skull evidence suggests a fish-based diet, indicating a largely semi-aquatic lifestyle, unlike modern anacondas that often prey on large mammals.