There are 20 reconstructed dinosaur fossils, some stretching across entire rooms, making this one of the best displays in the world.
"It is one of the largest exhibits in the world," said Dinosaur Exhibit Director Luis Chiappe. "And probably the most up to date, state of the art."
Some of the fossils were also found in California. The ocean-going dinosaurs roamed the waters that once covered the San Joaquin Valley.
"There are a number of things that you can see here that you're not going to see anywhere else," said Chiappe. "Spectacular specimens, but also spectacular displays."
The fossils also brought to light new information about the prehistoric creatures.
"The origins of birds from dinosaurs, the fact that some of these large dinosaurs were warm-blooded, a fact only discovered a week ago," said Director of Research John Long.
Some say the Tyrannosaurs Rex display is the prize of the collection.
"We've got the world's only growth series of Tyrannosaurus, one of the world's favorite dinosaurs," said Long. "Showing a 2-year-old, a 7-year-old, and a 14-year-old, going from a tiny little creature to something five tons in weight."
But you will also want to see the Triceratops, which greets you as you enter the exhibit. The dinosaur stretches 68 feet from head to toe.
"I love the Triceratops, it's just so emotional," said Long. "It's got this look of wisdom on its face. It's a beautiful specimen."
The museum opens to the public on July 16.