The big cats were rescued from Bolivia about two months ago and brought to a Wild Animal Sanctuary just east of Denver.
People working at the sanctuary have nursed the lions back to health and they're preparing the animals for the next step: exploring the outdoors.
Starting this week, they'll be allowed in new 20-acre outdoor habitats.
People at the sanctuary said the lions are ready.
"They're doing great, they've adjusted extremely well, they're gaining weight," said Katie Vandegrift of the Wild Animal Sanctuary. "We've seen, actually, a big difference in their demeanor as well."
The public will get to see the lions this summer.
