The Supermax facility outside Florence, in southern Colorado. 

(AP Photo)

The Colorado Department of Corrections will spend about $4.7 million to build outdoor recreation yards at the state's highest security prison.

The move is part of a settlement to a class-action lawsuit by prisoners at Colorado State Penitentiary in Canon City. They argued it was unconstitutional to deny inmates outdoor exercise.

A federal judge gave initial approval last week.

Amy Robertson of the Civil Rights Education and Enforcement Center, an organization involved the suit, says inmates will be able to use three outdoor yards at the prison. She says inmates used to exercise in what amounted to a concrete cell with a small opening to the outside.

Officials will also move the highest security inmates to a different prison in Sterling, where they will be able to exercise outdoors for the first time.