Zoo visitors will soon be greeted by life-size animatronic dinosaurs that roar, growl and move along a rainforest trail.

Oregon Zoo

Molds made from clay dinosaur sculptures are covered with liquid foam rubber to make this T. Rex's skin look more realistic.

Large footprints will guide guests and let them know how close they are to the ancient creatures. The path also includes fossil dig stations and photo opportunity spots.

The “Dinosaurs!” exhibit features 25 dinosaurs made up of 14 different species from the T. Rex to the two-foot tall Compsognathus. Slower moving herbivores, baby dinosaurs and egg nests are also part of the exhibit.

"T. Rex is the star of the show, of course," said Tony Vecchio, Zoo Director. "Stegosaurus, Triceratops, the long-necked Sauropods and all the popular carnivores are all represented. And some dinosaurs are just so funky that we had to have them -- like the dome-headed Pachycephalosaurus."

Each dinosaur was built on a steel frame and covered with foam-rubber skin. Scientists, artists and engineers teamed up to make them come to life. Electronics and air pistons move the creatures’ claws, limbs and teeth.

Visitors can also take a guided tour on their cell phone. Dr. Bones offers a virtual paleontologist’s take on the exhibit.

“Dinosaurs!” opens May 17 and will run through Labor Day. It costs $4 plus zoo admission.