Drive-in enthusiasts of all ages swung by American Canyon’s new Sonic Friday, where car hops on roller skates served the restaurant’s first slushies, fries and hamburgers.

Cars filed past the drive-thru window, as dozens of people placed orders on the patio at Napa Junction, where Wal-Mart opened a retail-grocery Supercenter a year ago. Classic cars were parked along the 17 stalls.

As people waited, carhops on skates and other employees without skates served slushies from Sonic’s 180,000-plus flavor combinations.

“Wow, I didn’t think it was going to be that popular,” said 13-year-old Geana Haddad, as she waited to order with her mother, Rima, older sister, Ashley, 14, and younger brother, Issa, 10.

Sonic, the only one in Napa County, will be open limited hours this weekend. Its first full day of operation is Monday.

Cherie Frink-Hunter of American Canyon came to see her two children on their first day at work at Sonic with her 17-year-old nephew, Sean Hunter of Fairfield.

The only Sonic he’s been to, said Sean, was in Sacramento. “I’ve been excited to come here forever,” he said.

Frink-Hunter said Sonic reminded her of the days she and her parents made trips to the local drive-in.

“It’s the ambiance mostly,” she said.

After the red-ribbon ceremony, American Canyon Mayor Leon Garcia predicted Sonic’s financial success.

“It’s going to be a big draw,” Garcia said. “We’ve proven business works here,” he added, referring to the city’s consumer sales tax dollars that are budgeted at $2.2 million this fiscal year.

The business will employ at first up to 50 people, including 25 full time, said Scot Cochran, director of operations for NorCal Restaurant Group LLC of San Francisco, the franchise owner. Sonic will be open 6 a.m. to midnight, seven days a week.

The American Canyon Planning Commission approved the project in April. Groundbreaking on the new 1,600 square-foot Sonic restaurant was early June. 

Kirk Hobbs, one of Cochran’s partners, said the highway traffic and the American Canyon community make Napa Junction an “outstanding location.”

Cochran this week said his company is considering opening new Sonic restaurants in other cities, including Brentwood, Antioch, Pleasanton, Santa Rosa, Oakley and Ukiah.

Based in Oklahoma City, Okla., Sonic has more than 3,300 drive-ins nationwide, according to the public company’s Web site. The closest Sonic is in Woodland, 44 miles away.