The centerpiece of Dinosaur National Monument is the Carnegie Dinosaur Quarry. On August 17, 1909, Earl Douglass of the Carnegie Museum of Natural History discovered the first dinosaur bones at this site. At first Douglass thought that they had discovered the remains of just one Apatosaurus (then called Brontosaurus). But as field work continued to uncover the bones of several different dinosaurs, it became apparent that they had uncovered a large and important dinosaur fossil site. Douglass and others with foresight sought to protect and preserve part of the site for observation by the general public. The Monument's quarry site is the result of that foresight. The original quarry building completed in 1958 had structural problems due to being built on unstable ground and was closed in 2006. A new building designed to properly deal with the environment was opened in 2011 allowing visitors to once again view the "Wall of Bones".
The new quarry building
The bones of the dinosaurs had been washed onto a level sandbar along a flooding river some 150 million years ago and then buried by subsequent flooding. Subsequent mountain building lifted and tilted the sandstone layer that now encases the fossils up to a 60 degree angle, making the exposed fossils a "wall of bones".
A very different kind of bench
A mounted cast of an Allosaurus found in the quarry
