The 161st Agricultural Fair opened Thursday morning in West Tisbury, a tradition that dates back to 1858. Nearly 2,000 people attended that first fair, which was held for one day on October 27, 1858, the traditional harvest season.

This year 10,000 people a day are expected to take part in the four-day summer festival, arriving from all over the Island and beyond.

The gates officially opened at 10 a.m. Thursday.

“Everything is going fabulously,” said Lena DeMoe, the fair’s ticketing manager, as she unpacked boxes of guidebooks destined for each entrance on opening day. “I think it’s going to be the best fair ever.”

Islander Evan Coogan arrived with her husband, two children and their grandparents. The fair, she said, is the perfect all-Island reunion.

“You run into half the Island while you’re here,” she said.

Diana Waring and her nine-year-old daughter Hazel made the trip from their West Tisbury home just down the street. The fried dough they shared left a dusting of powdered sugar on Hazel’s grin as she described her favorite ride: the Hang Glider.

Traveling to the fair from their home in New York, Nick and Katie Stein and their 11-year-old son Ollie looked on with a bit of trepidation at the rides.

“It’s awesome, and there are so many prizes, but all the rides spin, which isn’t always so good for my stomach,” Ollie said.

Mr. Stein attended the fair every year as a child and said that he is thrilled to finally share it with his son.

Other intergenerational fairgoers, Corrine Foster and her granddaughter, three-year-old Evy, wore matching overalls for the second year in a row.

“We figure it’s a good time to wear them,” Ms. Foster said. “We love the animals, the rides and seeing everything at the hall.”

Before the opening on Thursday, there was plenty of behind the scenes work that often goes unnoticed, which is the idea. Planning begins in October of the previous year, said Agricultural Society facilities manager Chris Lyons, adding that it is “controlled chaos.”

“Everybody has jobs to do, and everybody helps everybody else,” Mr. Lyons said. “It’s hard work every day.”

Vendors began arriving at the fairgrounds last Saturday to set up their booths, tents and trucks. While some vendors are local, others from off-Island stay with friends and family or in tents and trailers at the fair’s campground.

Patricia Jurawski made the trip with her Super Fried Chicken truck for the 20th year from her home in Danbury, Conn. She said that when she began working at the fair, vendors stayed in little campers and tents under bleachers next to the animal stalls.

“It gets to be kind of like a family,” she said. “Whether they’re a stranger or whatever, everyone is really cordial. It’s the way the world should be.”

Hawk Maddox, who works at the vegan and vegetarian stand Solar Cafe, said that the week leading up to the fair is a race to get everything in order for approval from a variety of inspectors, including the health inspector and fire chief.

Tom Colligan, who has been working at the fair as a wire inspector since 1977, said that he and the other inspectors, including West Tisbury fire chief Greg Pachico and building inspector Joe Tierney, fit together like a puzzle focused on safety.

“We are here to make sure people get home,” Mr. Colligan said.

Cushing Amusements has been operating the midway for over 30 years. A team of 50 stay in trailers on the fairgrounds, cooking and sharing meals and exploring the Island during their off hours the week before.

Mini-basketball operator Dareus Timias has worked for Cushing Amusements for over a decade since he was 13 years old. He works year-round, operating rides in warmer climates such as Miami and Puerto Rico in the winter.

Newcomer to the organization Chuck Taylor noted the close knit community that is formed on the fairgrounds.

“To put it into words, you couldn’t put it into words,” Mr. Taylor said. “It’s like a family. We carry each other when it gets hectic, which is all the time.”

Cushing Amusements owner Peter Cushing said the Ag Fair is a solid event, “all the way around,” but there are plenty of challenges.

“Out of all the events we do, I’d say this is probably one of the most difficult,” Mr. Cushing said.

Citing the high cost of living while staying on the Island, especially for food, he tries to make sure his staff, “the backbone of the operation,” doesn’t arrive too early.

The landscape of the Island also makes the event harder for staff.

“Anywhere else we go to, there’s convenience stores or there’s a gas station — somewhere to go to get a Coca-Cola or snacks,” he said. “Obviously, here there’s nothing within walking distance.”

Another crucial part of the fair’s success is its group of volunteers. Sakiko Isomichi manages the waste station, where she sorts recyclables and compost from trash. She began collecting food waste on the Island in 2016 and now works on a study that spearheaded the initiative at the fair.

“The fair creates a lot of trash,” she said. “I didn’t know that, and I don’t think a lot of people know that, but I think it’s a good way to do my part.”

All week long fair entries were submitted, from prize flowers to cucumbers, artwork, jams and pies. About two-thirds of the judging had been completed by Wednesday night, hall manager Janice Haynes said.

“So much rain this season meant that the fruits and the flowers are overflowing this year,” Ms. Haynes said. “We are thrilled.

On Thursday morning the judging continued, with a group evaluating cakes, brownies and cookies, and Liz Oliver’s pumpkin chocolate cookies.

“They can’t be rushed,” Ms. Haynes said.

Most of the judges have been doing it for more than 40 years, including Ann Burt, Jane Norton, Joe Sollitto and Janice Belisle.

“He’s new around here,” Ms. Belisle said, pointing to fellow judge Gary Blodgett.

Mr. Blodgett started judging in 1993.

As the day continued, the rides opened up and the smoke from burgers sizzling on the grill at the popular West Tisbury Firemen stand wafted through the air, mingling with the scents of fried dough, fried chicken and cotton candy.

After a busy summer working nonstop, Islanders greeted each other again, along with vacationers and daytrippers, young and old, creating a new temporary community each day.

“It’s fun, and everyone’s so open,” Mr. Lyons said, summing up the experience. “Most people have been doing it for years and the fair becomes kind of like a little reunion. You’ve got the oxen guys with their crock pots of stew and stuff eating together, and then you’ve got the horse guys who all get together and barbecue every night.”

For hours and daily schedules, visit marthasvineyardagriculturalsociety.org/the-fair.