Bill Irwin walks with this dog, Orient, as they end their 2,100-mile journey along the Appalachian Trail in Maine in 1990. (Bob DeLong/Bangor Daily News via Associated Press)

As he walked the length of the Appalachian Trail for eight months in 1990, Bill Irwin estimated that he fell thousands of times. He cracked his ribs and suffered from hypothermia as he climbed mountains and forded rivers. The pads he wore didn’t protect his scabbed knees.

Mr. Irwin, then a 50-year-old medical technologist and corporate manager from Burlington, N.C., did not use maps or a compass. He was blind, and he relied solely on his German shepherd guide dog, Orient.

The pair became known as “the Orient Express.”

Mr. Irwin was feted as an inspiration to hikers and disabled people when, on Nov. 21, 1990, he became the first blind man to traverse the Appalachian Trail, which stretches more than 2,100 miles, from Georgia to Maine.

Admirers across the country watched news reports of him dropping to his knees to pray after ascending 5,269 feet on Mount Katahdin, Maine, the northernmost end of the trail. Members of his home church were there to greet him and sang “Amazing Grace.”

For Mr. Irwin, who died March 1 at 73, the hike was an act of salvation.

“When I was a sighted person I was an alcoholic, a dropout as a husband and father, a guy who lived only for himself,” he later wrote in the publication Guideposts.

“The first clear-eyed thing I had ever done was as a blind man, when I asked God to take charge of my life,” he wrote. “I had never spent much time in his vast outdoors, but after I quit drinking I couldn’t get enough of it. I learned wilderness skills and became the first blind person to ‘thru-hike’ the Appalachian Trail from Georgia to Maine. I made a point of telling fellow hikers about the God who guides me.”

Mr. Irwin completely lost his sight in 1976. Eight years earlier, doctors had removed his left eye after a misdiagnosis of malignant melanoma. Meanwhile, his drinking became worse and he smoked five packs of cigarettes a day.

His unintended recovery was sparked by his son Jeff’s entry into a substance-abuse treatment center because of an addiction to cocaine.

“To my dismay, I was asked to spend a week there in family therapy sessions with him — without a drink,” he wrote in Guideposts. “I scoffed but I went. I lashed out at counselors and was my usual arrogant self. But by the end of that week it became painfully clear to me that I was an alcoholic, and I had to stop drinking or I’d die.”

He said he became sober in 1987 and developed an intense devotion to Christianity. The first verse he learned was from Corinthians: “For we walk by faith, not by sight.” He soon decided that the walk on the Appalachian Trail would be a powerful example of living his faith.

On March 8, 1990, the third anniversary of his sobriety, Mr. Irwin unceremoniously left from Springer Mountain, Ga., the southern terminus of the trail, in a heavy rain.

To cross rivers swelled with winter rain, Mr. Irwin would use the sound of Orient barking to find the shore.

“As I came out of the water, I could just feel the freezing take place in my hair,” Mr. Irwin once said, describing crossing a river at the end of his journey. “There was ice formed. By the time I got out, a solid sheet of ice had begun to form on my clothes. I knew that if I didn’t get to a safe place soon, hypothermia would overcome me and it’d be curtains for me.”

Along the way, Mr. Irwin would stop at grocery stores and laundromats to buy provisions and wash his clothes. He would also talk to local children about God and promise them personalized copies of the Bible if they agreed to read a verse a day.

“By the time I got to Maine I had furnished over 500 Bibles for kids along the way,” Mr. Irwin said.

He claimed he made the trip with no intention of drawing publicity. It didn’t work out that way. Reporters and TV crews would descend on him as word leaked out of his journey.

Dealing with journalists often tested what he called his God-

given patience. One New York City cameraman ordered him around for hours, while Mr. Irwin was wearing a 60-pound backpack and had a timetable to keep.

As he wrapped up, the cameraman asked why Mr. Irwin had been so helpful. Mr. Irwin confessed that he had wanted to throw a punch at the cameraman all day but that his faith helped him cope with such urges.

“When I said that, he fell on his knees [and said], ‘I want that in my life,’ ” Mr. Irwin later told the Charlotte Observer. “There wasn’t a higher moment on the trail.”

William Howard Irwin II was born Aug. 16, 1940, in Birmingham, Ala., where he graduated in 1964 from Samford University with a bachelor’s degree in chemistry and biology.

At 24, he founded a lab business that eventually became part of North Carolina-based LabCorp of America.

His first four marriages ended in divorce. In 1996, Mr. Irwin married Debra Messler. They moved to Sebec, Maine, from North Carolina and bought property with a view of Mount Katahdin. He died at a hospital in Dover-Foxcroft, Maine. The cause was prostate cancer, his wife said.

Besides his wife, survivors included three children from his first marriage, to Patricia Armstrong; a daughter from his marriage to Messler; a brother; a sister; and four grandchildren.

After the publicity from his trek, Mr. Irwin made a living as a motivational speaker and as a marriage, sex-addiction and family counselor. He also wrote a memoir, “Blind Courage,” written with David McCasland, with whom he walked parts of the final stretch of the Appalachian Trail. It sold more than 100,000 copies and was translated into Spanish, Chinese and German, the Charlotte Observer reported.

Mr. Irwin’s guide dog became the subject of “Orient: Hero Dog Guide of the Appalachian Trail,” a children’s book by Tom McMahon with illustrations by Erin Mauterer.