Pediatrician John DeLeonardis keeps busy, splitting professional hours between offices in Upper Deerfield and Mullica Hill. This father of four (including triplets) often sees upward of 150 patients a week. Registered nurse and wife Judith (or Jude as she prefers) is office manager.

Then, on his day off, Doc, as he is affectionately known, readily trades in his white lab coat and stethoscope for jeans, sneakers and a sweatshirt to head to his second job at the Delsea Drive­In Theater in Vineland.

"It's the only one in the state of New Jersey," boasts Doc, who bought the 171/2-acre property in 2004 as a buffer against the escalating costs of practicing medicine.

"I figured investing in the drive-in would not only give me and my family a little added financial security, but also let a new generation experience the same quintessential piece of American nostalgia that I and millions more grew up with in the 1960s," he said.

Mike Woeller, 32, for one, is glad to have the theater back. He manages Ritz Camera's Ellisburg Shopping Center store in Cherry Hill and grew up in Millville.

"I remember noticing the drive-in several times when it was closed, and I always thought how great it would be if someone were to renovate the property," he said. "Now as I pass by, it's kind of cool to know that it's up and running, not to mention being able to see the movies on the big screen from the road."

On Friday, the Delsea will celebrate the 75th anniversary of drive-ins, an idea patented June 6, 1933, by Riverton resident Richard Hollingshead. The party will include special food promotions and Camden Riversharks ticket and T-shirt giveaways.

By most accounts, Hollingshead, who worked as general sales manager at his father's store, Whiz Auto Products, conjured the idea to help his mother, a large woman who was never comfortable in standard movie-theater seats. The first drive-in opened on the Admiral Wilson Boulevard on the site now occupied by Zinman's Furs.

So contagious was this outdoor phenomenon that it sparked a craze that took the country by storm. At their peak in 1959, drive-ins numbered more than 4,700 nationwide.

But suburban sprawl, along with cable television, home entertainment systems and other factors took its toll, said United Drive-In Theatre Owners Association President Paul Geissinger, whose organization represents about 200 members.

The surviving drive-ins market their improvements over the years, including offering more first-run films such as

Indiana Jones and the Kingdom of the Crystal Skull

, which opened recently at the Delsea.

The Delsea Drive­In, under DeLeonardis' ownership, has become a family affair, with son John manning the box office and daughters Sarah and Rachael working in concessions. Mom also gets in on the act, pitching in wherever she is needed.

Four years and nearly $1 million in renovations later, Judy DeLeonardis admits that the drive-in, a 24/7 project, was a bit more than she initially bargained for, but she takes comfort in helping her husband's dream come to fruition.

Local filmmakers Chris O'Brien of Bensalem, Craig Dietzman of Hillsboro and Scott LoCicero of Doylestown quickly identified the Delsea Drive-In as a cool location to shoot several scenes for their soon-to-be-screened psychological thriller

Tapped

.

One subplot follows the ups and downs of the two central characters, Jimmy and Crystal.

"What better place to have a budding relationship develop than at a drive-in?" said co-writer Dietzman.

Will drive-ins endure another 75 years?

"Sure, there will be challenges ahead as we face an eventual conversion to digital projection, but it is important for us stick together," says Geissinger, who has run Shankweiler's Drive-In near Allentown for 25 years. Much of what drives drive-in operators is simply the labor of love, he added.

Just ask devotee John DeLeonardis.

Not only is he determined to perpetuate his drive-in, but now he has a skateboard park in the works.

If You Go

Delsea Drive-In, 2203 S. Delsea Dr. (Route 47), Vineland, 856-696-0011, Box office opens at 6:30 p.m. Friday, Saturday and Sunday. Beginning June 23, the drive-in opens daily. Adults $8; children 3-11 $3. Next weekend, films include

Indiana Jones and the Kingdom of the Crystal Skull

and

The Chronicles of Narnia: Prince Caspian

.

» READ MORE: www.delseadrive-in.com

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