Some call it Carnival, but in New Orleans the festive celebration is called Mardi Gras, and it's always a party--a big party. The season of Carnival starts on the Feast of the Epiphany, January 6, and culminates on the day before Ash Wednesday, otherwise known as "Fat Tuesday," which in French is "Mardi Gras." It is considered the last hurrah of feast and revelry before the start of Lent, with its 30 days of fasting.