The mass airlift marks an end to one of Britain's oldest firms.
Founded in 1841 by Baptist missionary Thomas Cook, the company sprang to life when he made it possible for 500 like-minded passengers to travel by train from Leicester in central England to a temperance meeting in nearby Loughborough.
It was "what the Victorians called rational recreation — not going to the pub and getting drunk — but doing things that were more uplifting," said Martin Daunton, an emeritus professor of economic history at the University of Cambridge.
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The trip was organized at the same time as the development of the railway across Britain. And in 1855, Cook branched out on his first European tour in which travelers visited Antwerp, Brussels, Cologne, Heidelberg, Strasbourg and finally Paris for the International Exhibition.
It was unclear Tuesday just how many customers in total had been affected by the company’s collapse. Reuters has reported that Thomas Cook currently has around 600,000 customers abroad and will need the help of governments and insurance firms to bring them back.
The CAA — the country's aviation regulator — said many of the vacationers were on Greek islands or in mainland Spain, while some were further afield in the Caribbean or North Africa.
The British repatriation effort is due to last until Oct. 6 with more than 1,000 flights planned to bring people home.
Richard Moriarty, chief executive at the regulator, warned customers that there would be some inconvenience and disruption but that as far as possible, they would attempt to bring travelers home on time.
“We want people to continue to enjoy their holiday, so we will bring them back to the U.K. on their original departure day, or very soon thereafter,” he said in a statement Tuesday.
As the focus begins to shift from the huge cleanup operation to what went wrong, emphasis is being placed on the company’s slow adaptation to the internet age.
"It was the first time that most people in Britain are starting to benefit from the industrial revolution," Daunton said. "People had the ability to have a stake in the benefits of industry rather than just being cheap labor."
But while an innovator credited with introducing the precursor to travelers checks in 1874 and a pioneer of the package tours, fast forward around 150 years and the company has struggled to cope with the rise of online booking sites and shifting travel habits.
This combined with a $2.1 billion debt pile, the sinking British pound — widely blamed on Brexit — and an unusually hot summer weather at home discouraging Northern Europeans from traveling appear to have added up to a perfect storm that led the 178-year-old company to cease operations.
Saphora Smith is a London-based reporter for NBC News Digital.
Cat Corrigan, Reuters and Associated Press contributed.