Looking for that pot o' gold at the end of the rainbow? Saint Patrick's Day (Irish: Lá ’le Pádraig or Lá Fhéile Pádraig), colloquially St. Paddy's Day or Paddy's Day, is an annual feast day which celebrates Saint Patrick (circa 385–461 AD), one of the patron saints of Ireland, and is generally celebrated on March 17. ( Edited by plmiller )  

http://en.wikipedia.org/wiki/Saint_Patrick's_Day