CHICAGO - Chicago's Field Museum has opened a rare display of mummies from its own collection. Many of them haven't been seen by the public since the World's Columbian Exposition, held in the city in 1893.

The exhibit is called "Opening the Vaults: Mummies" and runs through April 22. It features more than 20 mummies from Egypt and Peru, including complete humans and animals. Several will be displayed in their original 19th-century cases and some are 5,500 years old.

The museum obtained many of the mummies at the exposition in 1893, but they hadn't been studied thoroughly until last year because of fears of damage. Scientists at the lakefront facility performed non-invasive CT scans on several mummies, allowing them to "virtually unwrap" them.