let the good time roll
Mardi Gras is one day - the day before Ash Wednesday. Mardi Gras Season lasts about two weeks prior.
Mardi Gras parades start about two weeks before Mardi Gras day. The date of Mardi Gras changes each year since the date of Easter changes. Mardi Gras day always falls the day before Ash Wednesday.
The two are Fat Tuesday and Ash Wednesday (the first day of Lent).
This site is probably a good first stop: http://www.mardigrascostumes.com/ but there are many others which are equally sensible; http://www.costumecraze.com/Mardi-Gras.html and http://www.buycostumes.com/browse/Adult-Costumes/Mardi-Gras/_/N-3iZ27/results1.aspx are two.
This coming Tuesday, March 8th.
By no means are these the only two things - 1) Mardi Gras 2) Cajun food
The phrase "Mardi Gras" is of a French originality which means "Fat Tuesday." Mardi Gras season is called Carnival. The word carnival comes from two Latin words. They are carnem (meat) and levare (to remove). So carnival means "removing meat." Not eating meat was a common practice during lent
Tulane University was the first university in the state of Louisiana. They took the color green from the colors of Mardi Gras which are Purple, Green, and Gold. They then added white as there second color. When LSU went to pick colors they chose the remaining two colors of Mardi Gras being Purple and Gold.
it's a POS so only one
Maison Dupuy, New Orleans Hotel is only two blocks from bourbon Street so is a good choice for Mardi Gras but you'll want to book earlier. It also has a nice court yard for some privacy. The Dauphine Orleans Hotel is another good choice.
New Orleans has a huge one and Buenos Aires does too. Rio de Janeiro, Brazil, also has a notable parade.
If you are speaking of current events, two events come to mind... Mardi Gras and Jazz Fest. Both of these events are essential to the New Orleans economy.