SPRINGFIELD, Ill. (AP) — Illinois' renovated Governor's Mansion has reopened with Gov. Bruce Rauner and his wife, Diana, welcoming guests to the Springfield landmark.

Rauner is calling the reopening of the mansion Saturday a "great day for the state of Illinois." He said he and the state's first lady are "excited to invite the people of Illinois back to this historic facility."

A privately funded, roughly $15 million renovation began in early 2015. It included installing a new roof, HVAC system and entrance. Work also was done to ensure the mansion complies with the Americans with Disabilities Act.

The mansion now has a new visitor center. Guests also may view artwork and several exhibits, including one on Illinois life during the Civil War.

The building was constructed in 1855 and is the third-oldest state governor's residence in the U.S.

The mansion is now open for daily public tours.