There is an inland sea of sand that relatively few people realize exists. While the sand dunes of Death Valley National Park are fairly well-known, and most people are aware of the sand dunes at our national seashores, the towering dunes of Great Sand Dunes National Park and Preserve in Colorado are unknown to most.

Michael M. Geary brings these incredible dune fields to life in Sea of Sand, A History of Great Sand Dunes National Park and Preserve. Just released in March, this nearly 300-page book explores how these gigantic sand dunes, the tallest in North America, came to stand today, and how this landscape came into the National Park System.

The author comes to his task as a researcher and historian, as well as a writer. Some might fear this combination would result in a ponderous narrative, but it’s neither pedantic nor mind-numbing. But Mr. Geary is thorough, and leads us through various geologic processes that led to this spectacular field of dunes, the Native American tribes that crisscrossed the region, the Spanish explorers who came in search of gold, and the Americans focused on pushing the young country’s boundaries west. And, of course, he goes into great detail in laying out the push to preserve this incredible landscape as a unit of the National Park System and the growing pains the park endured.

That such a book is available to students of the National Park System is a credit to the University of Oklahoma Press that took Mr. Geary’s manuscript. In turn, Mr. Geary should be applauded for the effort he put into researching and writing about this unique national park.

Mr. Geary turns up wonderful 1930 correspondence between members of Colorado’s congressional delegation and then-NPS Director Horace Albright over the value of the sand dunes landscape as a national monument or park. The drive for preserving this unique landscape goes back into the 1920s, and involved the PEO Sisterhood, an “international women’s philanthropic and educational organization” that itself dated to 1869.

For true national park history aficionados, the author regales us with Roger Toll’s inspection and consideration of the sand dunes area for inclusion in the National Park System. Toll, although superintendent of Yellowstone National Park, also was Albright’s man in the field for assessing potential parks. During his career he had surveyed Death Valley, Joshua Tree, Big Bend, and even Everglades national parks for inclusion.

At the sand dunes, where Mr. Geary notes Toll spent a total of roughly “only about four to six hours … actually investigating the Great Sand Dunes,” Toll wound up producing a roughly 100-page report with maps, reports, photographs (“including several depicting the novel activity of skiing on the dunes”) that in the end spoke highly of including the area in the park system.

Great Sand Dunes, of course, did become a unit of the National Park System, first as a monument, then re-designated as a national park. But to understand the twists, turns, and trials that it took to get to that point, you should read this book.