100 years ago: The first scheduled international passenger flight departed

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On August 25, 1919, the first regular international passenger air service took place between London and Paris.

This fledgling flight, operated by Air Transport & Travel Ltd (AT&T) – a forerunner of British Airways (BA) – took off from Hounslow Heath, not far from what’s now Heathrow Airport, the British aviation hub where some 80 million passengers took to the skies in 2018.

Clearly, international flights have changed a lot in the past 100 years, so let’s take a look back at where it all began.

Aviation milestones

Courtesy British Airways/Amberley Publishing

Centenary celebrations: 2019 will mark 100 years of international air services operated by British Airways and its predecessor airlines -- including Aircraft Transport and Travel, pictured left, which operated what's considered the world's first daily international passenger, mail and parcel service -- between London and Paris in 1919. Pictured here: Aircraft Transport and Travel poster by MB, 1919, and Imperial Airways by an unknown illustrator circa 1926.

Courtesy British Airways/Amberley Publishing

Changing trends: 70-year-old Paul Jarvis, former Assistant Company Secretary at British Airways and now Curator of the BA Heritage Collection, has compiled a book of eye-catching posters from the past 100 years -- charting changing trends in aviation in advertizing. Pictured here: Imperial Airways poster by Steph Cavallero 1935 and Imperial Airways poster by Shurich, 1935.

Courtesy British Airways/Amberley Publishing

Public appetite: "The posters have always been a particular interest of mine," Jarvis tells CNN Travel. "We have about 1,200 poster artworks in the collection, and a few other quite important artworks as well." Jarvis felt there was a public appetite for these posters and decided to put them together in a book. Pictured here: Imperial Airways poster by James Gardner, 1938, and Imperial Airways poster by Stanley Herbert, 1935.

Courtesy British Airways/Amberley Publishing

Evocative images: Jarvis is the author of the new book: "British Airways: 100 Years of Aviation Posters," published by Amberley Publishing in association with British Airways. "There are so many evocative, gorgeous posters," says Jarvis. Pictured here: British Airways poster by unknown, 1936, and British Airways poster by Marshall Thompson circa 1936.

Courtesy British Airways/Amberley Publishing

Stunning showcase: In the book, Jarvis showcases the posters and provides context about the story behind them. "The very early days it was very much just about persuading people to fly at all," he reflects. "There were quite a lot of people who thought flying [...] was just a passing fad." Pictured here: British Airways poster by unknown artist 1936, and BOAC and Qantas poster by Stanley Herbert, circa 1947-50.

Courtesy British Airways/Amberley Publishing

Personal favorites: Jarvis says he can't choose a favorite poster in the book: "The front cover one I particularly like as an artwork in itself, by a very well known French artist Albert Brenet," he says. "But how do you choose, because there are many others like that as well." Pictured here: British South American Airways poster by Gwynn, 1946, and BEA poster by unknown circa 1949.

Courtesy British Airways/Amberley Publishing

Stunning designs: In a book full of stunning posters, there are some designs that stand out including the image on the right. The British Overseas Airways Corporation (BOAC), one of BA's predecessors, used Walter Herz's original Olympic artwork to promote traveling to London for the games. Pictured here: BOAC poster by Abram Games, 1948, and BOAC poster by Frank Wootton circa 1952.

Courtesy British Airways/Amberley Publishing

Explorations: Era-wise, Jarvis says the 1960s speaks to him from a personal level (that's the decade he started working at BA). "But from a purely [...] archival perspective it has to be the 1930s," he adds. "Because all the explanatory work that was [being done], new aircraft coming in." Pictured here: BEA poster by unknown, 1953, and BOAC poster by unknown, 1953.

Courtesy British Airways/Amberley Publishing

Global world: In the mid-late twentieth century, international aviation became more and more common. "An explosion of air services from 1946 when we started operating to New York because aircraft now had the range to reach it," says Jarvis. Trips to South Africa and Australia also became possible. Pictured here: BOAC poster by Bernard Sargent, circa 1953, and BOAC poster by Laban circa 1953.

Courtesy British Airways/Amberley Publishing

Cross-continental: These BOAC posters concentrate more on the destination than the aviation experience and were part of a series of posters released in the 1950s charting BOAC's cross-continental travel. Pictured here: BOAC poster by unknown, circa 1952, and BOAC poster by Eric Pulford, circa 1959.

Courtesy British Airways/Amberley Publishing

Romance and escapism: By the 1960s, posters were becoming more photo-led to match the growing popularity of TV advertising. These BOAC posters promote the romance and escapism of traveling abroad. Pictured here: BOAC posters by unknown, circa 1960s.

Courtesy British Airways/Amberley Publishing

Changing times: Jarvis says advertising has changed a lot since the golden age of travel: "It's so expensive to get print media out there, now, in any meaningful quantitative way, that reaches a wide audience," he says. "I suspect their heyday from the '30s,'40s, '50s, even the '60s, are probably long past and never will be repeated." Pictured here: BOAC posters by unknown, circa 1968.

Courtesy British Airways/Amberley Publishing

New beginnings: In the early 1970s, BOAC and BEA merged to become British Airways, the airline we know today. Pictured here: British Airways poster by Foot, Cone & Belding, now Draftfcb London Ltd, 1974.

Courtesy British Airways/Amberley Publishing

Concorde and club world: The early years of the newly re-branded British Airways celebrated the Concorde and the first fully flat bed for its Club World business class passengers. Pictured here: British Airways poster by unknown, circa 1976, and British Airways poster by M&C Saatchi, 2000.

Courtesy British Airways/Amberley Publishing

Continued innovation: Jarvis says advertising may have changed, but remains innovative. Take the London Olympics posters, for example: "No one can say they're not creative -- they're very simple, digitized images of athletes and aircraft. I think they're beautifully done," he says. Pictured here: British Airways poster by Bartle Bogle Hegarty, 2012.

1919 was a pretty action-packed year for aviation milestones; on June 15, British aviators John Alcock and Arthur Brown completed the first nonstop transatlantic flight, paving the way for the popular London to New York route passengers use today.

Still, 100 years ago, aviation was often the sole realm of brave adventurers and experienced aviators, so the daily London to Paris passenger flight, although it also transported mail and parcels, represented a new era in commercial flying.

AT&T’s marketing poster depicted iconic landmarks in each city: London’s St Paul’s Cathedral and Paris’ then-relatively new Eiffel Tower.

The glamorous ad also stressed the frequency of the new service – it departed daily, which seemed rather incredible at the time.

Paul Jarvis, the late curator of the BA Heritage Collection, who spoke to CNN Travel about his book “British Airways: 100 Years of Aviation Posters” in 2018, said marketing the first passenger air services was important.

“The very early days it was very much just about persuading people to fly at all,” Jarvis says. “There were quite a lot of people who thought flying […] was just a passing fad.”

After all, the first non-stop flight from London to Paris took place only seven years earlier, and the first powered flight took place just 16 years earlier.

Aviation was still a new game.

Early days of flying

The De Havilland DH4A G-EAJC aircraft, built for combat during the First World War and reimagined as a civilian airplane, made its way across the English Channel in a fairly swift two hours and 30 minutes. It was powered by a single Rolls Royce Eagle piston engine.

If you’re imagining a plane full of Brits ready to sample Paris’ baguettes and cheese, think again – it was a pretty small aircraft with limited, but intriguing, cargo.

Piloted by RAF veteran Lt E. H. “Bill” Lawford in an open-air cockpit, on board was one passenger, George Stevenson-Reece who was a journalist for London’s “Evening Standard” newspaper, plus a consignment of leather, two grouse and a few jars of Devonshire cream.

Stevenson-Reece paid 20 guineas for the journey (£21).

If that sounds like a good deal, bear in mind £21 in 1919 is equivalent to over £1000 ($1225) in today’s currency.

Weather conditions were apparently not particularly favorable, but the aircraft was greeted with enthusiasm by reporters and photographers upon landing in Le Bourget.

Later, flights on the service held up to 14 passengers.

Hot on the heels of the Brits, in 1920 Dutch airline KLM started flying aircraft between London and Amsterdam, and commercial aviation grew intermittently in the next few decades.

Still, it wasn’t until after the Second World War, Rolls Royce historian Peter Collins tells CNN Travel, that there was a “mindset change” that led to people embracing flying as a commonplace mode of transport.

“Although there were scheduled flights and aviation is developing and growing, it’s not massive […] It’s still for the well-off people,” he said.

Correction: This story has been updated to show the Alcock-Brown flight occurred in 1919.