Bill Cooke is one of only about 150 people each year who hike the entire Colorado Trail. His book, Shades of Gray, Splashes of Color, is a clear and honest look at what he experienced during 38 days and 482 miles of walking across the state.

The Colorado Trail is marking its 40th anniversary this year. Established in 1974, the trail runs from Denver to Durango. It was built by volunteers, completed in 1987, and maintained by the Colorado Trail Foundation.

While Shades of Gray, Splashes of Color includes plenty about the natural surroundings, the book’s strength is in its descriptions of the thoughts and hopes and satisfactions and disappointments that come with staying outside for that long, and really, doing nothing except walking each day, talking to other hikers, and making camp.

The trail runs along the mountains, and as Colorado residents well realize, the terrain changes along the way from almost alpine to southwestern. But as the terrain changed and went up and down – mostly up – Cooke’s determination to complete the journey, at age 63, remained steadfast. His description of the psychology of all those ups – the elevation varies from 5,520 feet near Denver to more than 13,000 feet near Coney Summit – is fascinating.

A retired accountant and manager with the federal government back East near Washington, D.C., Cooke provides a factual portrayal of what such a journey requires mentally and physically. Although he’s a lifelong hiker, this was by far the longest he’d stayed out on a trail at one time. As he made his preparations soon after retiring from his job, he wondered if he could do it.

The day he left in spring 2011, only a few minutes into his walk, he began to feel queasy and nauseated. Probably nerves, nothing most other hikers haven’t experienced. And although Cooke notes repeatedly that he is not an athlete, he does acknowledge that anyone engaged in such strenuous physical activity has good days and bad days.

He perseveres, sometimes hiking more slowly, and other times, more quickly than his companion, a lifelong friend nicknamed “Northern Harrier.” Cooke’s trail name is “Cookerhiker.”

Food, along with water and weather, is a constant concern when you’re hiking through the Rocky Mountains. Cooke’s other hobby, appropriately, is cooking, although you couldn’t tell that from his trail cuisine, which like many serious hikers is mostly some type of grain like bulgar wheat or couscous, boiled and eaten with a packet of tomato sauce or other flavoring.

At one point, Cooke forgets his food bag and has to survive on snacks for a couple of days – he doesn’t seem that disappointed.

Water, while available, is not always plentiful along the Colorado Trail. Some of Cooke’s best writing describes how we take water, which he often refers to as “agua,” for granted.

“As modern backpackers on a journey of recreation, we may differ in most respects from Ute Indians or early fur traders like Jim Bridger, but I’d like to think that our simple pleasures at savoring the refreshing libation from a mountain stream are identical,” Cooke writes.

He dutifully records the wildlife he sees – nothing too exotic, elk, moose, a few ptarmigan – but was more impressed by the colorful native plants of the high country. Modest to a fault, he notes he is no botanist, so other than mentioning them, he doesn’t go into detail on the flora or the fauna. He’s also not a historian, and doesn’t touch much on the past of the area along the trail.

He’s obviously comfortable writing about his inner journey, which is the most interesting part of the book and one that other hikers will identify with: “... what explains inconsistency? ... the real question is why don’t we accept and tolerate ‘inconsistency’ more? Is it because over 150 years of industrialization followed by the computer age inculcate us with the desirability of ‘normalcy’ of sameness, uniformity, homogeneity?”

His descriptions of geography, weather and other hikers will give readers a real feel for hiking the Colorado Trail, or completing any long-distance hike for that matter. However, a drawback is that the photos inside are black and white.

Although the trail is remote, Cooke meets plenty of interesting people along the way, often while hitchhiking into the nearest small town for supplies or passing through somewhere like Buffalo Creek or Kenosha Pass or Leadville or Salida or Silverton.

His retired status puts him into one of the two major demographic groups of long-distance hikers – athletic hippies and people who have quit working. (Many hikers fall into both groups.)

Completing the hike brought Cooke a great deal of satisfaction. In fact, he compared it to the birth of his daughters and passing the CPA exam on the first try. Really, the CPA exam? OK, as an English major and retired journalist, I found that surprising.

But that’s what you’ll discover in this book, Cooke’s honest account of what he felt and experienced. And if the CPA exam is a good metaphor for such an achievement, so be it.

A retired newspaper editor, Joe Stinnett is a freelance writer.