The idea for this adventure began last summer, when I read several books by people who hiked or attempted to hike the length of the Appalachian Trail. For the third or fourth time I started by re-reading “A Walk in the Woods,” Bill Bryson’s uproarious accounting of his trek, which eventually fizzled and failed. He completed the journey piecemeal, driving from one end-point to the next beginning. I nevertheless admired his gumption for even attempting it and delighted in his reporting of the days and nights on the trail. After all, it is more than 2,000 miles of grueling travel, taking most hikers six months of their lives to accomplish.

Sleeping on the hard ground with mice overrunning your sleeping bag in the middle of a fierce thunder and lightning storm, isn’t for everyone. Neither is piercing blisters or swatting at biting insects or tip-toeing around rattlers.

I knew I was not a candidate for a thru-hike, but I was fascinated and intrigued by the notion. It would be such an accomplishment, a feat of endurance and grit and determination. I could brag — modestly, of course — to friends and family.

In the fall, around the time of the 50th anniversary of the assassination of President John F. Kennedy, I was reviewing a summary of his administration when I was reminded of a challenge he had issued. He read of Theodore Roosevelt’s call to the Marines to march 50 miles, in full pack, as a show of military readiness. Kennedy reiterated the challenge for all the services and included his own staff. Younger brother Bobby, who served as JFK’s attorney general, decided on a whim to make the hike one weekend, wearing oxford dress shoes. He walked from Great Falls, Maryland, to Harper’s Ferry, West Virginia, in February of 1963, through snow and mud and less-than-ideal temperatures. I couldn’t help but wonder what his feet looked like at the finish.

Some of the public at large took up the challenge. Boy Scout troops organized 50-mile hikes for merit badges. To this day, the hike is re-enacted each February by at least one group.

That, I thought, was a challenge I could accept. I’m already an inveterate walker, logging five to seven miles a day — once in a while 10, if I’m feeling feisty. I figured I could walk from home to my son’s house, twenty-five miles away, have a light lunch and rest break there, then turn around and come back. Fifty miles — nothing to it.

How long would it take, though? I wondered. I could average 3 ½ miles an hour on a 10-mile hike; I knew that. If I could maintain pace, that would mean a walk of a little over 14 hours, not counting breaks. I assumed I’d need 15 to 16 hours to make the march. I’d want to do it in the light of day, as much as possible, so the likeliest time would be in June, when the days are their longest. I took the rest of the winter to keep in shape and work on endurance, incrementally lengthening my daily walks.

As spring approached, I settled on a different route. Rather than walk to my son’s and back, I decided on a shorter course that successively would be repeated 16 times. Dirigo Drive, in Brewer, is a well-known track for an annual 5K race. I could park my truck at one end and use it as a “base camp” of operations. I wouldn’t need to carry much in a pack, just some water, since I could keep other provisions — extra socks, even shoes, sandwiches, juice — in the bed of the truck. Yeah, the hike would get boring with 16 repetitions, but I thought that at some point in a walk of 50 miles, the scenery loses its allure anyway. How prophetic that insight turned out to be.

It was that on a recent Saturday morning, I parked at the top of Whiting Hill, got out, stretched a little and started walking. It was balmy and beautiful. And even though the road is central to urbanization, I was reminded I was close to nature. A northern flicker paced me on the opposite side of the street, hopping on the curb and peeking over the now-gone-by dandelion heads. Eventually he flew off to examine the trunk of a dead tree. A young fox skittered lightly across the road well in front of me, grasping firmly in its jaws what appeared to be a starling. Buttercups, daisies and Indian paintbrushes were in blossom in the tall grass abutting the sidewalk. The few vehicles out at that time of the day were moving slowly toward their destination, in no hurry. It was a fine day for a walk.

After seven or eight miles of appreciating nature, though, I found myself alone, thoughts turning inward, reflecting on events current and past. Like the time a college friend and I decided to climb Mt. Washington on a Labor Day weekend. At the base of the mountain, it was a splendid late-summer day, and we were comfortable in our sneakers, jeans and flannel shirts. As we neared the summit, though, we found ourselves scaling a rock field in near-blizzard conditions. We were lucky to locate the weather station. Once dried out and warmed up, we mooched a ride down the hill with a middle-aged couple who felt sorry for us. Washington has an auto road as well as a cog railway, so the less-hardy may ascend the summit. It’s likely the only way I’ll ever see it again.

We were super-stupid, extremely fortunate and deserving, I suppose, of their pity. Back on Dirigo Drive, though, 12 miles into the hike, my feet, swollen and sore, started to complain. These feet, these same feet that played basketball five times a week until they were in their mid-40s, often with inadequate sneakers, were hurting.

Many of those games in the early days were played in a friend’s driveway, where the asphalt is less forgiving than hardwood. No mas, no mas, my feet cried.

At 20 miles, my pace had slowed. At the start of the day, I was making one leg of the course in 48 to 50 minutes, but I was now taking over an hour. The sights and the sounds, the birds and the breeze, were no distraction from the simple, mind-numbing monotony of taking one throbbing step after another. The pleasant morning turned into more than mere drudgery; it became an exercise in sheer pain absorption.

In the end, 25 miles proved to be my limit. My apologies to President Kennedy; I gave it 100 percent of my effort but only achieved 50 percent of the goal. I’m not that disappointed, though. I figure 25 miles for a 65-year-old body is still an achievement, one that can’t be dismissed lightly, I don’t think — or taken too seriously, either, come to that. After eight hours I went home to a cold shower and an even colder beer.

As for Bryson, he may well be my literary and intellectual superior, but we do have one thing in common: we both know when to quit.