Ask any owner — a corgi has something no other dog has.

“Do you see that butt?” said Jonathan Wong. “Now that’s a butt.”

Wong was pointing to the business end of his corgi, who answers to Bentley and who was one of no fewer than 1,000 corgis who brought their pleasing posteriors, along with the rest of the package, to the north end of Ocean Beach on Saturday for their annual convention.

It’s called Corgi Con, and it’s been going for five years. That means five years of corgis in sunglasses, corgis in propeller beanies and corgis in ballet tutus.

The beach was overrun with the tan, friendly low-lying dogs. Just about every corgi fan except Queen Elizabeth II showed up.

“We invited her,” said Corgi Con organizer Cynthia Lee. “I guess she has more important things to do.”

Hard to believe anything could be more important than corgi costume pageants, corgi races and corgi ninja warrior contests. Or the chance to buy any number of shirts, mugs and pins with corgi butts — not faces but butts — plastered on them.

The corgi butt coffee mugs, at $16, were moving faster than most corgis. After the first hour, mug salesman Jason Foo was practically sold out.

“Should have brought more,” he said. “Nothing I can do about it now.”

A corgi named Gracie, with her eye on the costume pageant blue ribbon, was dressed as Elton John. Last year she was dressed as a loaf of Wonder Bread and won second place, but second place isn’t good enough for a dog like Gracie and especially for her owner, Haley Losberger, who had driven all the way from Sacramento with a pair of pink Elton John sunglasses.

Being a sensible animal, even though a corgi, Gracie tried to shake them off until Losberger made it clear that sunglasses were part of Gracie’s man’s-best-friend duties for the day.

“She loves ’em, really,” said Losberger, while Gracie — who has her own Instagram page, like most corgis of any account — tried to.

A corgi named Furgie, who was sniffing Gracie’s business end, has an Instagram page, too. Hers has 500 followers, more than most people.

“She’s short and fluffy, with a big butt,” said her owner, Tania Landeros. “She’s magical.”

Melissa Looney came from Davis with her corgi named Franklin, who was dressed in a propeller beanie to please his fans. Franklin has been featured in a $20 photo book called “Where’s Franklin,” in which you have to find not Waldo but Franklin. Proceeds go to corgi rescue, although most corgis are too cute to go unrescued for long.

“We’ve sold 2,000 books,” Looney said. “Not bad for a goofy dog like Franklin.”

Alaina Roberts, 14, of Los Gatos was there with her corgi, Sparrow. She named him Sparrow in honor of movie pirate Jack Sparrow, because the dog was born on International Talk Like a Pirate Day. It was an explanation that made perfect sense to nearby fellow corgi owners. Her parents bought Sparrow for Alaina last Christmas, after Alaina floored them with a pro-corgi PowerPoint presentation. A corgi, she said, is worth the effort.

“Corgis look really funny,” Alaina said. “But corgis don’t know they look really funny.”

The corgis were incredibly well behaved and tidy. Their humans came equipped with handfuls of plastic bags, to make sure the National Park Service would continue to sign off on Corgi Con for next year. The humans themselves were relegated to eight Porta Pottis, and at times there was a line to use them, which proves that dogs have it better than people in many respects.

Vendors abounded. Some sold cigars for dogs ($3 each) and some sold beer for dogs ($4 a bottle) and some sold hand-woven planter boxes in the shape of corgis ($40 for a small one and $60 for a big one).

Javier Jasso was selling socks for corgis, at $14 a set. Remember, he said, with a set of dog socks you get twice as many socks as with a set of human socks.

“It comes to $3.50 a sock,” he said.

About the only dog on the premises that wasn’t a corgi was Bella, who is a springer spaniel. On most days, a springer is considered a cute enough dog, no further pumping up needed.

“Well, I think she’s better looking than a corgi,” said her owner, Barbara Eagle of San Anselmo. “She’s got a great personality. That’s important. She’s got a lot more going for her than just a butt.”

Steve Rubenstein is a San Francisco Chronicle staff writer. Email: srubenstein@sfchronicle.com Twitter: @SteveRubeSF