A 100-year-old tragic cave accident led to this national park. Here’s what happened.

MAMMOTH CAVE, Ky. — During a late January tour of Mammoth Cave, the guide clapped his hands, and the already dim lights went out.

He had brought our group to a stop in a flat area – like a small plaza in a hollow section of limestone – to tell us how cave explorer Floyd Collins got trapped nearby almost 100 years earlier. As he described how Collins knocked his lantern over while trying to get out, 20 or so other visitors and I were enveloped by the underground darkness.

The pitch black, darker than any I’ve ever seen, lasted for about 30 seconds, but Collins was trapped for over two weeks, dying before rescuers could reach him. Thursday marks a century since his entrapment, an incident that helped lead to the creation of Mammoth Cave National Park. Here’s how.

Who was Floyd Collins?

Collins is considered “one of the greatest cave explorers of all time,” according to the National Park Service. He discovered Great Crystal Cave in 1917, which his family ran as a show cave on their farm in what is now Mammoth Cave National Park.

During the Kentucky Cave Wars – when cave owners in the area competed fiercely for tourist dollars – Crystal Cave’s location off the main road led Collins to search for a more convenient site.

While scoping out nearby Sand Cave on Jan. 30, 1925, the 37-year-old got stuck on his way out. As he twisted and squeezed through tight passageways, his foot bumped against a loose rock, and the nearly 30-pound mass fell on his ankle.

“The way I describe it to visitors is, imagine stepping in a bear trap and it closing on you, and you just can’t pull yourself out of it,” Cave Guide Jackie Wheet told a group of media outside Sand Cave last week. Icicles dangled over the entrance – which is closed to the public – on the 38-degree morning, and there was snow on the ground. The conditions during our tour were similar to those Collins saw the day he was trapped, according to Wheet.

A furious rescue effort began and word spread among neighbors and local media, eventually drawing reporters from across the country, which reached a fever pitch on Feb. 8, 1925.

“It’s a Sunday afternoon, and the media circus is so bad that they nicknamed it ‘Carnival Sunday,’ ” said Wheet. “They estimate about 10,000 people were out here.”

The National Guard was sent in to do crowd control, according to Wheet, and the American Red Cross set up tents. “They were more or less treating people drinking too much moonshine than they were treating people digging in the rescue shaft,” he said.

Rescuers finally reached him through a vertical shaft measuring 55 feet to find he had died. Collins had been trapped for 18 days.

The shaft was closed due to safety concerns, Wheet said, but his body was removed after it was reopened months later.

How did Floyd Collins help create Mammoth Cave National Park?

After the National Park Service was established in 1916, Congress began considering new places for national park designation. With many already located in the western U.S., a study was commissioned to review potential sites elsewhere, such as the Great Smoky Mountains and Shenandoah, according to Dr. Rickard Toomey, a Cave Specialist with the park. Mammoth Cave was also “somewhat considered,” he said.

“The idea had been talked about on and off throughout the years,” Wheet added. “But you know, World War I happens, and people kind of forget about it.”

While Sand Cave is not part of the Mammoth Cave system, Collins’ entrapment and the widespread attention it generated brought the area “back to the consciousness and got it on the list,” according to Toomey. The park was authorized by Congress in 1926 and officially established in 1941.

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“We like to say that Floyd Collins did have a connection with this becoming a national park, even though that wasn’t his goal,” said Wheet.

His legacy has lived on in other ways, too. Singer Vernon Dalhart memorialized him in his hit song, “The Death of Floyd Collins.” Collins’ Crystal Cave, which remained a tourist destination until the 1960s, also became part of the national park in 1961.

This spring, a musical about Collins will make its Broadway debut. Previous versions of the show ran in Philadelphia and later Off Broadway in the mid-1990s, The New York Times reported.

‘The national park helps preserve his legacy’

In honor of the anniversary, visitors can attend special events at the Lodge at Mammoth Cave’s Rotunda Room next month.

The Life and Tragic Death of Floyd Collins will take place on Feb. 21 at 6:45 p.m., and the Floyd Collins Discussion Panel with Subject Matter Experts – including Collins family members – will be on Feb. 22 at 6:45 p.m. Both are free, and no advanced signup or tickets are required.

Guides also frequently cover Collins’ story on regular cave tours and during other programming.

Toomey said “having Mammoth Cave National Park include Floyd Collins as one of the central stories that we tell here at the park helps keep his story alive.”

“So, he helped create the national park, and the national park helps preserve his legacy.”

Nathan Diller is a consumer travel reporter for USA TODAY based in Nashville. You can reach him at ndiller@usatoday.com.

This article originally appeared on USA TODAY: How a tragic accident led to the creation of this national park