On a gorgeous night, some 4,000 people, dressed all in white, have come to dine in a public, yet secret place in New York's Bryant Park.

They have come for Diner en Blanc, an unusual pop-up event that takes place in 20 countries. The guests eat in splendor at a location they only learn about minutes before they arrive. The thousands wave white napkins to signal the beginning of the event.

They arrived at 6:30 in the evening last Wednesday, carting white tables and chairs, china, food, wine glasses and cutlery. This is the third year that Diner En Blanc has come to New York.

Laura Tyring, who has traveled down from White Plains, stands in a line with her friend, Monica Condor, rolling her cart as the queue moves slowly, carrying a big straw basket filled with supplies. She wears a white shirt, white pants and and a big, white, lacy, floppy hat. How long ago did she learn the secret location of this event?

"A minute," she says. "They gave us several locations where to meet."

Attendees are told to wear comfortable shoes and have a subway card. They meet a team leader who says,"follow me," and they don't learn the location until they are almost there.

Fitting more than 1,800 tables into Bryant Park means pushing every table very close together. The chaos of setting up flows into organization and beauty: fine white china; white napkins, sometimes folded into intricate designs, flowers — white lilies and roses; little electric candles that would not blow out in a wind.

And, of course, the clothes: wedding dresses, styles from the '20s, people wearing white angel wings. Sandy Jarrett came here with her daughter, Michele.

"It's all about the adventure," she says. "It's about lugging all the accoutrements to some unknown destination, and then getting there and seeing all these adventurers in white. It's magical."

The co-hosts of this New York event are Sandy Safi and Aymeric Pasquier, who also run the international organization. "It baffles me every time to see how much people invest into this," Safi says.

But she says it works because it's spontaneous and different, and it gets back to basic values we forget in the bustle of city life, "sharing a meal with friends, getting dressed up."

Diner en Blanc started 25 years ago, when Francois Pasquier, Aymeric's father, decided to hold a dinner party in the Bois de Bologne, a large public square in Paris. Since some guests were bringing along friends, he asked everyone to wear white so they would be able to spot each other easily.

These days, Safi says, Diner en Blanc takes place in 40 cities around the world. But interest exploded after New York hosted its first event three years ago, Safi says: Since then, some 400 cities that have requested Diner en Blanc to come to them.

Pasquier says part of the appeal is the effort that's required to participate.

"Most of the events now, you just pay a price and you're passive," he says. "In Diner en Blanc, it's [just] the opposite. You work a lot, you have to bring your own table, you have to bring your own chairs, so you commit, and you have to bring back your garbage. All this work is like an achievement, and you will see the joy of people tonight."

A few minutes later, I'm walking through the lines of white tables when an acquaintance, Leslie Brown, calls out to me. She is at a table for six, filled with glorious-looking food and several bottles of wine.

"What's on the menu," I ask? She tells me: salmon, an assortment of cheeses, roasted cauliflower and peas, a rice salad with portobello mushrooms, skewers of shrimp and, of course, lots of wine and desserts.

Then, just as I am about to leave, Brown says, "Are you going to sit down and eat with us? We have an extra plate. We have enough, and I have an extra knife and fork."

So I sit down on a very low box — there are no extra chairs — and take a skewer of lovely grilled shrimp and some of that portobello salad and a little of that dish of cauliflower and peas. And I join the conversation.

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