“Dirty Dancing” is about to turn 20, and what once appeared to be a cheesy chick flick seems to be gaining the status of “Casablanca.”

Made for $3 million, it has grossed more than $200 million to date. A commemorative DVD is coming out in May and a stage version is breaking records in Europe. The show is headed to Toronto this fall, Broadway in ’08. Producers want the rights in Dubai.

Why such universal appeal?

Is it the dancing? The sound track? The Cinderella story, where the plain Jane sister gets the prince — or at least the sweaty hunk in tight pants? (Works for me.)

My friends, its hidden power lies in all of those, but also in its setting: the Catskills.

“By setting the film in such a family-oriented place, it makes the transgressiveness” — the breaking of cultural taboos — “even greater,” Manhattan psychiatrist Harvey Roy Greenberg said.

Vacations are always about transformation. We leave home secretly hoping to leave our old selves behind, too.

That’s a lot harder to do, however, when one is vacationing with one’s parents. After all, they usually a have a very firm notion of who their children are, and usually it’s not “darling moppet on the brink of a frenzied sexual awakening.”

Most parents want their children to stay children, or at least be obedient, and that was one of the appeals of the Catskills. It’s where Jews went to keep things — and romances — predictable. Traditional.

“People went up there for romances,” the head of the Catskills Institute, Phil Brown, said. “A waiter or busboy would likely be Jewish and a doctor or lawyer in training,” he said. Parents, just like the ones in the movie, were happy to see their daughters date them.

The non-Jewish staffers, however, were off-limits. When Baby (Jennifer Grey) stumbles upon this group dirty dancing, the thrill hits her like a pelvic thrust. And yet she still wants to be daddy’s good little girl. She’s torn.

The fact that in the end she gets both — a sizzling pas de deux with Patrick Swayze and the eternal love of her proud papa (Jerry Orbach) — is what makes the movie so powerful. It’s the heartwarming tale of a girl who teaches her parents the evils of prejudice (see Disney, Every Movie Ever Made By). But it’s a coming of age tale, too, complete with fantastic (albeit allegorical) sex. (See Cable TV, Every Movie After 3 a.m.). It’s two, two, two great movie formulas in one!

And the backdrop just intensifies it all.

“People really relate to the Catskills experience,” the star of “A Jew Grows In Brooklyn,” Jake Ehrenreich, said. “There’s something about vacation time, at a resort, with your family that’s a bittersweet time in our lives.”

Maybe in Dubai they don’t know from Grossinger’s. But they do know from children longing for their parents’ approval even as they’re pulling away. They need “Dirty Dancing,” too.