Think poodle skirts, saddle shoes and flattops.



And, oh yes, 15-cent hamburgers.



It was the era of innocence, innovation and the birth of rock ’n’ roll.



The 1940s and ’50s also saw the birth of the Golden Arches, an icon that revolutionized the restaurant business.



And then they super-sized it.



Right in San Bernardino.



On May 15, 1940, brothers Dick and Maurice “Mac” McDonald opened McDonald’s Barbecue Restaurant in San Bernardino, at 1398 N. E St., a popular hangout for teens because it was so close to San Bernardino High School.



In 1948, they closed their successful restaurant, terminated about 20 car hops and reduced the extensive menu to cheeseburgers, hamburgers, milkshakes and fountain sodas.



Then, they revamped their kitchen in order to specialize in speedy service — literally fast food.



A year later, they offered fries with that.



Their forward-thinking vision forever changed the restaurant industry.



The site of the original McDonald’s is now home to the Original McDonald’s Museum, opened in 1998 by Albert Okura, founder of the San Bernardino-based Juan Pollo chain of restaurants.



“I never thought I could own this property. I was in the right place at the right time and I took action,” Okura told me.



“The McDonald brothers were the Henry Fords of the restaurant business and passed the savings on to the customers. McDonald’s is the greatest thing to come out of San Bernardino,” he said.



The McDonald brothers opened their first restaurant adjacent to the Monrovia Airport in 1937. It was a tiny octagonal building informally called the Airdrome. Because they couldn’t afford the rent at that location, they had the building cut in half and put on two flatbed trucks and hauled to San Bernardino at the site of the current museum, at 14th and E streets.



That was 75 years ago, and to mark the anniversary, artists Phil Yeh and Rory Murray will be at the McDonalds museum making additions to the historical mural. Tours of the museum, a designated historical landmark, will be available.



The property also features the original offices of the McDonald brothers, which later served as an area to air-dry the french fries before they could be immersed in the frying oil.



“We’ll be at the museum doing a replica of the museum on the mural and should be there between 11 a.m. and 5 p.m.(today,),” Murray said.



The museum is jammed with all things Mickey D — the Hamburglar and his jail; Ronald, of course, looking kind of creepy in some of his earlier manifestations; early menus; the prototype of a ketchup-dispensing gun; even Speedee, the restaurant’s first mascot.



Route 66 plaques, newspaper articles and photos chronicle the growth of the fast-food giant.



“We tried to make a personal connection with the people who contributed and put things on display,” said Okura. “The museum is also reflections and stories.”



Then-San Bernardino Mayor Judith Valles and city spokeswoman June Durr helped make the museum a reality, he added.



In 1961, Dick and Mac McDonald sold the proprietary rights to McDonalds to Ray Kroc for $2.7 million, netting the brothers $1 million each. A lot of money at the time, but it was a bargain for Kroc, given the unprecedented success of the business.



These days, there are more than 30,000 McDonald’s in 119 countries.



The global icon is the subject of a movie ramping up in Atlanta this month. “The Founder” centers around Kroc, and how he saw the franchise potential in the McDonald brothers’ fast-food preparation and turned it into a billion-dollar empire,



The film, scheduled for release in November 2016, stars Michael Keaton and Laura Dern.



The irony? Because of California’s tax credit incentives, the filming takes place in Georgia and a replica of the museum will be built there, according to Okura.



A long way from the booming little hamburger stand in San Bernardino.



This article has been updated from an earlier version to correct the date of the film’s release. It is scheduled to be released in November 2016.



Michel Nolan appears in The Sun on Wednesdays, Fridays and Sundays. Reach her at michel.nolan@langnews.com or on Twitter @MichelNolan.

