Near Cleveland, Utah, in the San Rafael Swell, the Cleveland-Lloyd Dinosaur Quarry holds the densest concentration of Jurassic dinosaur bones ever found: more than 16,200 bones excavated so far, and many thousands more still waiting in the ground. How they got there is a mystery. The bones belong to many different species, and they lie disarticulated and jumbled together. In 1980 Peter Dodson proposed that the place was a predator trap, but an extreme drought now seems the likelier cause, and scientists have not reached a consensus. The quarry became a National Natural Landmark in 1965 and a National Monument in 2019. The Bureau of Land Management runs its visitor center, renovated, expanded and rededicated in 2007, where a reconstructed adult Allosaurus stands among the exhibits; it is open seasonally, with hours that vary.
The densest concentration of Jurassic dinosaur bones ever found · Jurassic, Morrison Formation
This ground is protected. Photograph it, record it, leave it where it lies. On US federal land the Paleontological Resources Preservation Act 2009 makes collecting vertebrate fossils an offence, and penalties are real.
Other places on the map within a couple of hours.
