The New Orleans Carnival season, with roots in Catholic ritual, starts on Twelfth Night (January 6). The season of parades, balls (some of them masquerade balls), and king cake parties begins on that date.
From about two weeks before, through Fat Tuesday, there is at least one major parade each day. The largest and most elaborate parades take place the last five days of the season. In the final week of Carnival many events large and small occur throughout New Orleans and surrounding communities. Mardi Gras is French for Fat Tuesday.
The parades in New Orleans are organized by Carnival krewes. Krewe float riders toss throws to the crowds; the most common throws are strings of cheap colorful beads, doubloons (aluminium or wooden dollar-sized coins usually impressed with a krewe logo), decorated plastic throw cups, and small inexpensive toys. Major krewes follow the same parade schedule and route each year.
While many tourists center their Mardi Gras season activities on Bourbon Street and the French Quarter, none of the major Mardi Gras parades enter the Quarter because of its narrow streets and overhead obstructions. Instead, major parades originate in the Uptown and Mid-City districts and follow a route along St. Charles Avenue and Canal Street, on the upriver side of the French Quarter.
To most New Orleanians, "Mardi Gras" refers only to the final and most elaborate day of the Carnival Season; visitors tend to refer to the entire Carnival as "Mardi Gras." Some locals have thus started to refer to the final day of Carnival as "Mardi Gras Day" to avoid confusion.
The traditional colors of Mardi Gras are purple, gold, and green. These are said to have been chosen in 1892, when the Rex Parade theme "Symbolism of Colors" gave the colors their meanings. The colors in turn influenced the official colors of Louisiana State University (purple and gold) and Tulane University (blue and green). Before and during Mardi Gras, purple, green, and gold fabric is certainly the most popular colors to wear all at once.