Workers are installing a titanosaur skeleton cast of "Maximo," the largest dinosaur ever discovered, starting Wednesday through Friday.
His name is Spanish for "Maximum" and was named for its enormous size and Argentinian homeland. The bones were so big that a crane had to hoist part of it through the museum's front door.
When fully constructed, the structure will be 122 feet from head to tail, which is longer than two accordion CTA buses.
"It's gonna reach the balcony level," said Peter Makovicky, the dinosaur curator of the Field Museum.
Maximo will take over the spot where Sue the Tyrannosaurus Rex stood for the last 18 years.
Sue was dismantled in February, and has been reassembled in its own exhibit on the second floor.
Sue's size pales in comparison to Maximo, a massive 70-ton plant-eater discovered in Argentina.
"Imagining a herd of 70-ton animals is mindblowing," said Makovicky.
Maximo is actually be a cast of a titanosaur. The bones are fiberglass, allowing for an interactive exhibit.
But that's not the only new feature - new hanging gardens will have hundreds of live plants.
"About every 20 years or so Stanley Field Hall gets kind of a face lift, or a redo. A few years ago there were different dinosaurs, there was Sue. Before that, there were even fountains in Stanley Field Hall," said Hilary Hansen, Project Manager.
Museum visitors took it all in on Wednesday, enjoying the work in progress.
Annette Delgado asked her son, Diego, if he liked dinosaurs. Yes, he nodded.
The Defatta family though, visiting from Shreveport, Louisiana, had hoped to see Sue.
"A little disappointing, because i was telling the kids we could see some big dinosaur exhibits. but I understand things are changing and we're still excited to be here," said Jennifer Defatta.
Maximo will be fully assembled by Friday. After that, all the barriers and scaffolding will be removed by June 1, when you can walk under him and touch the titanosaur.