Rocks deposited during the latest part of the Cretaceous period (75 to 65 million years go) yield abundant bones and eggs of dinosaurs. Bones and nests are being discovered in the soft Cretaceous soil to the west of the town.
Large scale palaeontological excavations have been carried out in the vicinity since 1989. In 1992, this scientific research resulted in the establishment at Espéraza of the first museum solely dedicated to dinosaurs in Europe. It is located in the old railway station at Espéraza and displays 35 different species.
A palaeontology workshop initiates children (6-12 years olds) into archaeological digging and skeleton reconstruction. 5 minutes away, near Campagne, the largest archaeological digging area in Europe is open to the public for guided tours. Volunteer excavators are also welcome.
Eva, an Ampelosaurus specimen, the most complete dinosaur skeleton ever found in France and was discovered in deposits around 72 million years old at Campagne-sur-Aude, close to the Dinosaur Museum in Espéraza. The animal is estimated be around 12 meters long, 2.5 meters tall and weighing 10-15 metric tons. It appears to be juvenile, as some adult bones found in the area are about twice as large. The specimen was discovered in August 2001 by Eva Morvan, a geology student who provided the nickname "Eva". The find was a major media event in France, and made the national newspapers in the UK.
Excavations at the Bellevue site are carried out during July and August by volunteers.