Alexander L. Morton in Nepal in October 1994. (Photo by Janice Berger)

Alexander L. Morton, a Harvard-trained transportation economist who one day gave up his career for what he called a “joyous but chaotic” life of travel and ad­ven­ture, died Oct. 12 at his home in Washington. He was 70.

He died of a brain tumor, said his sister, Janice M. Berger.

At 42, Mr. Morton was well on pace in the ascension of his chosen career ladder. He had a doctorate in economics from Harvard, had taught at the Harvard Business School and was finishing a four-year assignment as director the office of policy and analysis at the Interstate Commerce Commission.

He then quit.

He had made enough money in real estate deals and investments to guarantee an independent income for himself. For his remaining 28 years, he was almost constantly on the move, visiting dozens of countries and often going off the expected paths from Western travelers.

On bicycle, he pedaled the length of the four main islands of Japan. He hiked in the Himalayan mountains, explored the game preserves of Africa, followed the headwaters of the Mekong River into Vietnam, climbed Mount Sinai at dawn and rode a train from Moscow to Beijing. On the spur of the moment, he once set out to climb Mont Blanc in the Alps, and he reached the summit wearing only sneakers as footgear.

On his far-flung journeys, Dr. Morton rarely had a fixed itinerary, according to a traveling companion, John Harbert, a physician who taught at Georgetown University Medical School and served at the National Institutes of Health.

Dr. Morton wanted to meet and get to know local people, and he generally used local transportation, anything from airplanes to sailboats. He slept wherever he could, in a ferry boat hammock on a journey up the Amazon River, on a makeshift cardboard bed in an African bus station.

He took a 15-day trip through Iran and returned to tell friends that while Americans were regularly denounced by the mullahs, he himself had received warm and friendly welcomes from most ordinary Iranians.

He hiked up as far as a base camp on Mount Everest. He was stranded in the Sudanese desert near Khartoum for two days with scant food and water when the train on which he was traveling stopped for reasons that are less than clear.

He was riding through a Zambian game preserve once when the small rented car in which he was traveling turned a corner only to find two rhinoceroses and a cub rhino directly ahead and not looking pleased.

“Back up,” Dr. Morton shouted to his driver, only to discover that a herd of elephants had suddenly come up behind them. Discreetly, the driver drove off the road and the animals wandered off.

Alexander Lyall Morton was born Feb. 6, 1943, in New York and raised in Glen Rock, N.J.

He graduated from Amherst College in 1965, then spent two years in the Peace Corps in Ethiopia. He went out on morning horse rides and, according to his sister, on several occasions greeted another rider — Ethiopian Emperor Haile Selassie.

Dr. Morton received a PhD in economics from Harvard in 1973 and then taught at Harvard Business School before being named special assistant to the chairman of the Civil Aeronautics Board in Washington. He held other jobs and, in 1979, joined the ICC, leading an office working on the deregulation of trucking, railroad and bus industries.

Many summers during his traveling years, Dr. Morton found time to relax at Orleans on Cape Cod, where his family had vacationed since his childhood. Survivors include his partner of 31 years, Thomas A. Pursley of Washington; a sister; and a brother.

He rarely spoke about himself and never discussed in detail his reasons for retiring in mid-career as an economist to pursue a life of travel. But his sister said he was ready for a change, had the savings to and had done as much as he wished to in the field of transportation deregulation.

To continue along the same path, would have been a case of “been there, done that,” she said.

CORRECTION: This story has been revised to include Mr. Morton’s surviving partner, Thomas A. Pursley.