There is no historical marker. No sign. No gravestone.

Luckily for me, Chuck Eckman is still agile in his early 80s, setting the pace as we walk up a dirt road and across a mowed hayfield in a swampy stretch of northeastern Minnesota 3 miles west of Moose Lake.

In a stand of birch trees, Eckman stops and leans against an ink-black opening into what, a century ago, served as the Soderberg family root cellar. The 6-foot-high igloo of stone morphed into a mausoleum on Oct. 12, 1918.

When I punch the flashlight app on my phone and step into the clammy cellar's blackness, I'm swept back to one of the darkest years in Minnesota history — and the subject of my new book: "Minnesota 1918: When Flu, Fire, and War Ravaged the State" (Minnesota Historical Society Press).

The three calamities that converged on 1918 Minnesota — fires Up North, war in Europe and the deadly flu pandemic — killed thousands but also revealed the resiliency of everyday Minnesotans. Many of them were immigrants from Finland, Poland, Germany and Scandinavia. The first World War claimed 1,432 Minnesota soldiers in the trench warfare and mustard gas of Europe. Another 2,326 soldiers from the state died in the deadly flu pandemic, which spread through troop transfers in waves across the globe — killing an estimated 50 million people, including roughly 12,000 in Minnesota.

Just as the war ground to an end in France and flu deaths spiked, a bone-dry summer and railroad sparks combined to ignite an October wildfire that killed more than 450 people — leveling the cities of Cloquet and Moose Lake and a dozen other communities in a sprawling burn zone that covered 1,500 square miles in seven northeastern Minnesota counties.

The 1918 fire remains Minnesota's deadliest natural disaster. And more than 100 people lucky enough to survive were crammed into evacuee housing, where they contracted the flu and died.

"The pitiful tragedies and thrilling escapes reported were so numerous," Duluth weatherman Herbert Richardson wrote in a 1919 report, "that any attempt at detailed description of them would fill a volume."

Chuck Eckman's is one of the many voices that keep the stories of 1918 alive — joining accounts of long-forgotten nurses, soldiers, lumbermen, farmers, doctors and politicians from across the state. And Natalie Frohrip is just one of countless people who serve as caretakers of the stories from 1918.

During a research trip to Moose Lake, I was having lunch with Frohrip — the tireless director of the Fires of 1918 Museum housed in the city's old Soo Line train depot. It was one of the few buildings to survive the fire.

"Have you talked to the Eckman brothers?" she asked.

A half-hour later, after a cold-call knock on their door, I was sipping coffee and munching cookies with Shirley and Chuck Eckman. A longtime auto body repairman in the Moose Lake area, Chuck and his twin brother, Jim, still live on their grandparents' old homestead — another of the rare structures that withstood the inferno.

"They thought the fire would blow over the top of them, see," Chuck says after leading me to the Soderberg cellar in the woods. "But it sucked right in."

Sons of Swedish immigrants, Charley and Axel Soderberg had spent that summer fretting about their brother, David, fighting in the Great War in France. But the horrors over here rivaled the bloody warfare "Over There."

By the time David Soderberg came home, nearly all his relatives were dead and buried in a mass grave in Moose Lake — including a dozen nieces and nephews, ranging from a newborn to 16-year-old Hilma Soderberg. They'd followed their parents into this root cellar to escape the massive forest fire swallowing up the countryside. They were discovered the next morning in this tomb of stone. Potato sacks had been strung up in the cellar's doorway — a final, failed attempt to save themselves.

Back at the Eckmans' home, Shirley digs out a book detailing what happened to Chuck's great aunt, Agnes Eckman Peterson, on Oct. 12, 1918.

Pregnant at 33, Agnes sprinted over to a neighbor's home when the fire swept through the area. Her husband, Albin, had gone to fight the fires. Authorities found her body a few days later in a well, covered with charred wood debris, along with five members of the neighbor family. They'd climbed in the well to try to save themselves.

"Just the skull was recognizable," the Superior (Wis.) Telegram reported. "The buckle of her dress she was wearing at the time was identified as hers."

As grim as the stories from 1918 can be, they also show the bounce-back spirit of a 60-year-old state. And much of the action a century ago is eerily similar to today's headlines — with wildfires in California, American soldiers in far-off hot spots and the number of flu deaths alarmingly high this year.

One of the most telling quotes is tucked in a Dec. 31, 1918, biennial report, in which Minnesota Adjutant General Walter Rhinow quotes an unnamed soldier returning home after the fire:

"I had thought that the devastation wrought by the retreating Germans was of such calibre that I would never see anything to exceed it," he said. "This burnt-over area is so completely extinguished of all semblance of human occupation that the deliberately destroyed territory deserted by the Germans was almost a Paradise in comparison."

Curt Brown's tales about Minnesota's history appear each Sunday. Readers can send him ideas and suggestions at mnhistory@startribune.com. For more on his new book, go to tinyurl.com/MN1918.