See how stars such as Dolly Parton, Kate Middleton, Catherine Zeta-Jones and more celebrated St. Patrick's Day on.

Monday, March 17 is St. Patrick's Day, celebrating all things Irish in the U.S. and around the world. Cities celebrate with parades, bar crawls and more.

St. Patrick's Day was once a solemn religious holiday . Irish culture and heritage experts previously have told USA TODAY the holiday was once a solemn religious day, but it start ...