Only about 50 people have visited all 419 areas of the National Park System, and just one has written a book about those travels.

David Kroese made all his treks in about five years, traveling to national parks, monuments, battlefields, military parks, historical parks, historic sites, lakeshores, seashores, recreation areas, scenic rivers and trails and the White House – some places more than once.

By the time he reached all of them, he had started to compile a book, “The Centennial: A Journey through America's National Park System.” Tuesday evening the St. Louis native, who now resides in the Chicago area, shared the story of part of his travels with a small audience at the National Frontier Trails Museum in Independence.

Kroese's presentation on centered on National Park sites along the Western trails that originated from or near Independence, including several forts, landmarks such as Chimney Rock and Lewis and Clark expedition sites.

“I thought it would take decades,” Kroese said of his National Park odyssey, which started in 2012 and finished in 2017, a year after the National Park centennial. “I thought 20 years at best.”

“It really accelerated when I found like-minded people. I had more than 300 heading into 2016.”

The odyssey started rather innocently, when he and his wife, a naturalized citizen, visited the Civil War battlefield in Chancellorsville, Virginia. A career chemical engineer with a long interest in history, Kroese said he thought he might take that day's commute to explain the historical significance of the site.

“She rolled her eyes,” he said. “The only thing she got out of it was 'David is very happy to be here.'”

But his wife also noticed a passport book of all National Park areas and thought that might interest him.

“Little did she know what she was starting,” Kroese said. “The National Park System will take you through American history. The parks and the trails have layers and layers of history.”

Kroese, who got married at age 40 and does not have children, joked that he spent what might have been savings for children's education on his travels. He also was able to step back from his chemical engineering career and take a telecommuting position.

During the centennial celebration year alone, he visited all but 24 sites, many of them for a second time. His travels included trips to Puerto Rico and the Virgin Islands, Guam and American Samoa. It required an extended summer stay in Alaska, where four NPS sites are above the Arctic Circle and only a few of 23 in the state are accessible by road.

“That required a lot of planning,” he said.

The book started after some prodding from his mother to put together a permanent memento of his travels. He now travels and gives presentations based on his book full time. Kroese also mounted a display of commemorative pins that have traveled to Park System locations for others to enjoy.

“People so friendly and inviting,” he said of his visits to NPS sites. “I wanted to do something to give back and say thank you.”

Kroese also hopes he can help people feel a greater sense of appreciation and preservation for the parks.

“I hope everyone can feel a sense of ownership with the parks,” he said. “We're all park stewards. If there's one thing that's true, what's not protected will go away.”