SAVANNAH — It's time for Savannah's most profitable holiday of the year — St. Patrick's Day.

The celebration fills the streets of Georgia's oldest city with thousands of tourists who show up thirsty, whether or not they're truly Irish.

The sprawling parade started in 1824 by Irish immigrants to the Georgia coast kicks off Thursday morning. Hotel managers and bar owners in the city expect the revelry to continue through the weekend.

Some bars plan to begin pouring at 7 a.m. Thursday, a full three hours before the parade begins. They won't close until last call at 2 a.m. Friday.

Savannah last studied the economic impact of St. Patrick's Day a decade ago, when the celebration on the cobblestone riverfront alone was estimated to bring in $30 million. Turnout on peak years has been estimated at up to 400,000 people.