The wreckage of an 11-car passenger train is shown in the Florida Keys in September 1935 after the train was derailed by a hurricane that claimed the lives of more than 400 people. (AP)

It was Labor Day, Sept. 2, 1935, when the nation’s first-recorded Category 5 hurricane struck the Florida Keys. The winds: between 200 and 250 miles per hour. The storm surge: 15 feet high. Thirty miles of a railroad track connecting a portion of the archipelago was decimated. Hundreds died, including more than 200 World War I veterans working on an overseas highway linking the Keys.

When survivors and rescue workers surveyed the damage, they were horrified by what they saw: people buried or partially entombed in muck and mangroves, bodies dangling off trees. One family reportedly lost 50 members.

With Irma headed toward South Florida, officials in the Keys — a series of islands set off the southern coast have ordered mandatory evacuations. Hotels are shutting down, the airport was expected to halt operations, and residents and tourists began their trek along the single highway back to the mainland.

But the fear in the Keys isn’t just a matter of geography: Back in the late summer of 1935, when the country’s weather forecasters didn’t have satellite technology, some residents and government officials in the Keys were taken by surprise by the viciousness of the hurricane. It has haunted residents ever since.

The storm was first detected in late August 1935, about five days before landfall, according to “Category 5: The 1935 Labor Day Hurricane” by Thomas Neil Knowles. It was expected to pass between Key West and Havana. Even by Labor Day morning, evacuations hadn’t been ordered yet.

By afternoon, the barometer was rapidly plummeting. And now a new question emerged: When should a train be sent to rescue the hundreds of World War I veterans working on the overseas highway along the Keys? In the event that the hurricane would ever directly approach the Keys, officials had already planned to send a Florida East Coast Railway train along the islands to bring the veterans back to the mainland, north of Miami.

But during the morning and early afternoon of Labor Day, government officials got word from the U.S. Weather Bureau suggesting the hurricane would not pose a danger to the Keys. So the rescue train kept getting delayed, according to Knowles’s book. It wasn’t until late in the afternoon when the hurricane was clearly headed to the Keys that officials ordered the train to get moving.

“Bureaucratic red tape and an apparent lack of concern delayed the train’s departure,” Jay Barnes wrote in his book, “Florida’s Hurricane History.”

The rescue train managed to arrive in the Keys in the evening. Many veterans boarded the train, but it was too little too late.

The nameless storm — hurricanes didn’t receive official monikers until the 1950s — swept the train off its track, killing many of the passengers. Photos of the tossed train show it lying on an island, twisted on its side. The hurricane destroyed much of its track, and the railroad was never rebuilt. Knowles was quite blunt about the storm’s impact: “Hundreds of people of all sexes, ages, callings, and physical conditions were either killed outright by objects propelled by the wind and surging water or were drowned when they became trapped in collapsing buildings or entangled in lime trees or mangrove branches.”

Several days later, on Sept. 9, the New York Times reported that government officials had declared that “negligence played no part in the failure to evacuate” the World War I veterans from their relief camps. The article’s headline: “Hurricane Deaths Laid to Act of God.” Accompanying the story was a photo of what appears to be coffins set afire, with smoke billowing out. “A FUNERAL PYRE IN THE STORM SWEPT FLORIDA KEYS,” the caption read. “For the protection of those who survived, the bodies of veterans who were killed in the hurricane were ordered burned.”

Other storms have been deadlier. The 1900 Galveston hurricane in Texas was the worst, killing more than 10,000 people. The 1928 Okeechobee Hurricane was Florida’s most devastating, wiping out more than 2,500 people. But the Labor Day hurricane in the Keys was more powerful.

“For a long period of time, it was considered one of America’s greatest hurricanes. It still is,” Barnes said in an interview with The Post.

When John Platero, an Associated Press reporter, wrote a story about the hurricane in 1985 on its 50th anniversary, he found one 67-year-old Keys resident named Bernard Russell. The man’s cousin had been found 40 miles from their home town, “still holding her baby in her arms,” he said.

What still bothered Russell 50 years later?

People who don’t take hurricanes seriously.

“The most foolish thing is to have a hurricane party,” he said. “Only an idiot would have one.”

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