The Messel Pit is a disused quarry located in the municipality of Messel in Hesse, Germany. It is known for its abundance of well-preserved fossils from the Eocene Epoch, including plants, mammals, birds, reptiles, and insects. The site was designated a UNESCO World Heritage Site in 1995, as it provides an exceptional record of the evolution of life on Earth during the Eocene.

The Messel Pit was formed approximately 48 million years ago as a deep lake, surrounded by tropical forests. Over time, organic matter, such as leaves and animals, sank to the bottom of the lake, where they were covered with sediment and preserved in the anoxic environment. The result is a unique and diverse collection of fossils that provide insight into the evolution of various species during the Eocene.

Since the quarry was abandoned in the 1970s, the site has become a popular destination for scientists and tourists alike. The fossils found at the Messel Pit have helped to expand our understanding of prehistoric life and are considered one of the best-preserved fossil records of the Eocene. A visitor center at the site offers guided tours and exhibits, allowing visitors to learn more about the history and significance of the Messel Pit.