It’s normally a faux pas to wear the same outfit as someone else to a party, but for a New Orleans day of drinking and running called the Red Dress Run, only a little red dress will do.

Runners both male and female, in red dresses of all shapes and sizes, will once again strut their stuff in the streets on Saturday for the 21st annual New Orleans Red Dress run to benefit more than 100 local charities. The day begins and ends with parties, with the run in between.

“New Orleans is just so conducive to a good time,” said Bill Healy, general manager of the New Orleans Hash House Harriers, the organizers. “The motto of the Hash House Harriers is ‘We’re a drinking club with a running problem.’ There’s an awful lot of drinking that goes on.”

The party includes entertainment by Dash Rip Rock and The Breton Sound, unlimited beer and a catered barbecue lunch for registered participants. After the run, there is an after party from 4 p.m. to 1 a.m. at the House of Blues with drink specials and live music. Only registrants are allowed from 4 p.m. to 8 p.m., after which the party opens to the public.

The Red Dress Run originated as a “hashing” run in San Diego. Hashing is a hare-and-hounds style run where the “hare” leaves a trail with false leads that the “hounds” must follow.

“The first Red Dress Run was kind of an accident,” Healy said. “A hasher had a friend come out to visit and she showed up to the hash in a red dress. She wasn’t really dressed for running, but she did it anyway. … The year after that, they did a hash where they all wore red dresses to commemorate that one event. It kind of took off.”

New Orleans is home to the largest Red Dress Run in the nation, as other runs are typically hasher-only events. Healy said he does not know of another one that includes non-hashers.

“Some of the first ones there were only maybe 50 or 60 people that participated,” Healy said. “Then as it took off and we started opening it up to non-hashers; it just blew up. We’re going to have about 7,000 registered (this year) and last year we had just over 6,000.”

Registration is $70 in advance and $80 the day of the race. Packet pickup and registration are available at the Red Dress Run expo from 4 p.m. to 9 p.m. Thursday and Friday at the Fairgrounds Racetrack grandstand building. The expo will offer beer, sell red dresses and allow participants to skip the line Saturday morning. Registration also will be available from 9 a.m. to 1 p.m. on the day of the event on Rampart Street in front of Armstrong Park. More information is at nolareddress.com.