The Messel Pit (German: Grube Messel) is a disused quarry near the village of Messel, (Landkreis Darmstadt-Dieburg, Hesse) about 35 km (22 mi) southeast of Frankfurt am Main, Germany. Bituminous shale was mined there. Because of its abundance of fossils, it has significant geological and scientific importance. After almost becoming a landfill, strong local resistance eventually stopped these plans and the Messel Pit was declared a UNESCO World Heritage site on 9 December 1995. Significant scientific discoveries are still being made and the site has increasingly become a tourism site as well.
The Messel Pit was the setting for the WWB episode, New Dawn, during the Eocene. At that time, it looked very different from how it looks today: much more luscious and tropical. It was populated by giant ants, flightless birds and strange, basal mammals - most of which died out when the Eocene ended.