Send home the clowns.

After 146 years, the curtain is coming down forever on “The Greatest Show on Earth.”

Ringling Bros. and Barnum & Bailey Circus’ last performance will be May 21 at the Nassau Coliseum.

The show stoppers included high operating costs, declining attendance and changing public tastes.

Not to mention a long and costly legal battle with animal rights advocates, which ended with its hugest stars — the elephants — being pink-slipped. Elephants had been the symbol of the circus since an Asian pachyderm named Jumbo joined the show in 1882.

Employes were told the sad news Saturday night in Orlando.

The circus will perform 30 more times. Besides the show on Long Island, there will be one in Brooklyn. Other stops on its last tour include Atlanta, Washington, Philadelphia and Boston.

With its exotic animals and death-defying acrobats, the big top had been a huge draw from the mid-1800s to the mid-1900s.

Phineas Taylor Barnum had made a traveling spectacle of animals and human oddities popular, while the five Ringling brothers performed juggling acts and skits. Eventually, they merged and the modern circus was born.

Its clowns, acrobats and horseback riders — along with their animals — were transported across the country in special cars on extra-long trains.

New York staged its own yearly spectacle. When the circus came to town, the performers, along with invited guests, rode elephants from the Sunnyside rail yards through the Queens Midtown Tunnel and then along Manhattan streets to Madison Square Garden.

In its heyday, the circus attracted huge crowds. It had such a glamorous image that kids famously dreamed of running away from home to join.

But as years passed, children grew less enchanted.

First blockbuster movies, then television and finally, video games and the internet captured the circus’ core audience — both the youngsters and their parents.

“The competitor in many ways is time,” said circus owner Kenneth Feld, adding that transporting the show by rail and other circus quirks — such as providing a traveling school for performers’ children — are throwbacks to another era.

When the Feld family bought the circus in 1967, the show was just under 3 hours. Today, it’s 2 hours and 7 minutes, with the longest segment — a tiger act — clocking in at 12 minutes. “Try getting a 3- or 4-year-old today to sit for 12 minutes,” Feld said.

Feld and his daughter Juliette Feld, the company’s chief operating officer, acknowledged another reality that led to the closing, and it was the one thing that initially drew millions to the show: the animals.

In May 2016, the company removed the elephants from the shows and sent them to live on a conservation farm in central Florida.

In 2014, Feld Entertainment won $25.2 million in settlements from groups including the Humane Society, ending a 14-year fight over allegations that circus employees mistreated elephants.

Attendance has been dropping for 10 years, said Juliette Feld, but when the elephants left, there was a “dramatic drop” in ticket sales. While many said they didn’t want big animals to perform in circuses, many others refused to attend a circus without them.

The Felds said their existing animals — lions, tigers, camels, donkeys, alpacas, kangaroos and llamas — will go to suitable homes.

In recent years, Ringling Bros. tried to remain relevant, hiring its first African-American ringmaster, then its first female ringmaster, and also launching an interactive app.

“We tried all these different things to see what would work,’’ said Kenneth Feld. “We weren’t successful in finding the solution.”

With Associated Press