The Brief Hurricane Katrina devastated New Orleans and the Gulf Coast region on Aug. 29, 2005. Friday marks the 20th anniversary of Hurricane Katrina, one of the worst natural disasters in the nation’s history. What happened in Hurricane Katrina? (Photo by Mark Wilson/Getty Images)Dig deeper:On Aug. 29, 2005, Hurricane Katrina devastated New Orleans and the Gulf Coast when it made landfall as a Category 3 storm. File: Two men paddle in high water after Hurricane Katrina devastated the area, August 31, 2005 in New Orleans, Louisiana.