Seventy-five years ago today, back when Airport Circle still had an airport, the first drive-in movie theater opened in Pennsauken, where Zinman Furs now stands.

By combining America's passions for cars, movies and passion itself, inventor Richard Hollinghead Jr. of Riverton spawned a cultural phenomenon that took off after World War II, peaking in the late 1950s.

He even patented the invention, though he had little luck collecting royalties, according to a nephew, Wick Hollingshead, 69, of Clarksboro, N.J.

Marking today's anniversary will be many of the 400 or so drive-ins left across the nation - including the three within 70 miles of Philadelphia.

Shankweiler's, near Allentown, is doing its part just by continuing to show first-run movies. In 1934, it became the second drive-in, making it the nation's longest-operating. No hoopla is planned, says owner Paul Geissinger, although its website notes it's in its 75th season.

Saturday night, Becky's, a bit north of Allentown, besides having two twin-bills of first-run blockbusters, will have fireworks and introduce this season's kid-friendly amusements, including pony rides, a fire engine, and a moon bounce.

Tonight, Saturday and Sunday, Vineland's Delsea Drive-In - the closest to Center City and the only drive-in in New Jersey - will have early laser shows, a moon bounce, and giveaways, including T-shirts and tickets to Camden River Sharks baseball games.

After Kung Fu Panda and the new Indiana Jones will be a third feature, an independent psycho-thriller, Tapped, some of whose scenes were shot at the drive-in, said owner John DeLeonardis, a pediatrician.

Soon, the drive-in will add a second screen, he said.

The next-nearest drive-ins are Mahoning Valley, north of Becky's; Diamond State Drive-In, near Dover, Del.; and Bengie's, outside Baltimore.

The number of drive-in peaked at 4,063 in 1958, according to the United Drive-In Theatre Owners Association.

Families packed their Ramblers and Impalas with squabbling siblings to park alongside grappling/groping teenagers in those days when TV shows were black and white and Playboy was considered hard-core smut.

Wives Beware seems like a fitting title for the first feature at the "World's First Automobile Movie Theatre," as ads called the original drive-in.

For 25 cents, plus two-bits more per person, up to a max of $1 per vehicle, people could "sit in your car and enjoy talkies" while parked in "individual driveways three times the length of your car," ads proclaimed.

The sound blared from speakers near the screen, which annoyed the neighbors, Wick Hollingshead said.

Today's drive-in-goers pick up the soundtrack via car and portable radios.

The original idea, he said, may have come from his grandmother, Donna, the inventor's mother.

A large woman who disliked cramped movie theater seats, she remarked one day that she wished she could park her car in a movie theater, her grandson said.

Perhaps that's why one of the early ads had a drawing of a portly woman edging into a row of theater seats, declaring, "Even Kate Smith would no trouble finding a seat at the world's first automobile movie theatre."

The original enterprise only lasted a few years.

In the early days, drive-ins "had a hard time getting first-run movies," he said. ".. It took them a long time. They get some good movies now."

By 1940, the site - some sources say it was off Crescent Boulevard (Route 130), others Admiral Wilson Boulevard - had become the home of Zinman's, which still stands there today.

A move to have a commemorative plaque put up has the backing of DeLeonardis and the United Drive-In Theatre Owners Association, Hollingshead said.

Contact staff writer Peter Mucha at 215-854-4342 or pmucha@phillynews.com.