In a celebration millions of years in the making, this October the Smithsonian National Museum of Natural History in Washington, D.C. will receive its first-ever authentic Tyrannosaurus rex skeleton.

The T. rex skeleton will eventually be the centerpiece of a new $35 million dinosaur hall planned to open at the National Museum.

"If you've ever stood next to a real T. rex skull, you'll realize what a breathtaking thing it is: four feet long, with teeth the size of bananas," said paleontologist Kirk Johnson, Sant Director of the museum. "It is the most terrifying carnivore that's ever lived on the planet. And it really makes you ponder what life would have been like with these things prowling the North American landscape."

Thursday the museum announced it reached a 50-year loan agreement to display the skeleton known as the "Wankel T. rex." With 80 to 85 percent of its fossilized bone recovered, Wankel is one of the most complete T. rex specimens on the planet.

In 1988, Kathy Wankel, a rancher from Angela, Mont., found the fossilized bones on federal land near Fort Peck Reservoir in northeastern Montana. While on a boating trip, Wankel stopped on an island in the reservoir to have a look around and found the bones, which were later taken to a museum and identified as the first arm bones belonging to a T. rex ever discovered, the Smithsonian reported.

Until 2011, the skeleton had been on display at the Museum of the Rockies at Montana State University and it will return from the National Museum to Montana after the end of its 50-year loan, according to a report from local Bozeman, Mont. news station KBZK.

The fossil is expected to arrive in the nation's capital, appropriately enough, on National Fossil Day, Oct. 16.

But before it is put on display, the museum will digitally scan every bone of the dinosaur to produce a virtual record of the T. rex. Once fully digitized, the data can be used to print replicas - from full-size to desktop - of the dinosaur. However, the process will take a while; only parts of it will be showcased until the entire thing is put on display in 2019.

With more than 7 million visitors annually, the National Museum of Natural History is the most-visited natural history museum in the world.

"We're thrilled to welcome this extraordinary fossil to the Smithsonian," museum director Johnson said, according to KBZK. "The Wankel T. rex will be the most viewed T.rex fossil in the world, and we wish to extend our sincere appreciation to the U.S. Corps of Engineers, the Museum of the Rockies and the Wankel family for all they've done to make this possible."