Correction appended.

It was an odd and hauntingly beautiful forest to be lost in. The trees were growing on pure dark lava, their roots often stretching above the ground and wrapping around caverns, making it difficult to walk. The tree cover was so dense that G.P.S. devices sometimes didn’t function, and there were hundreds of long ropes tied to tree trunks.

Pieter ten Hoopen grabbed onto a rope and made his way down an incline with a sense of foreboding. He was uncertain what he would find at the end of the 300-meter blue rope. He knew there might be clothing, empty pill containers and a diary, a scene suggesting that a suicide had taken place. Reaching the end of the rope, he was relieved there wasn’t a body or human remains.

After all, there is reason the Aokigahara Forest, at the base of Mount Fuji, is called the “suicide forest.”

Japan has more than 30,000 suicides a year — one of the highest rates among industrialized nations. On average, someone in Japan dies by his own hand every 15 minutes. Usually a man. The Aokigahara Forest is the most common place to commit suicide in Japan, and it is widely thought to be the second most likely site in the world, after the Golden Gate Bridge in San Francisco.

The reasons are complex.

In 1960, Seicho Matsumoto wrote a popular novel called “Tower of Wave,” in which a couple commits suicide in Aokigahara Forest. These woods are described as the “perfect place to die” by the author Wataru Tsurumi in the book, “The Complete Manual of Suicide.” His best seller has been found next to many bodies in the woods, which is also known as the Yukai Forest, or Sea of Trees.

Pieter ten Hoopen/Agence Vu

In addition, Mount Fuji is revered as a sacred site in Japan. Folk tales tell of ghosts and demons haunting the forest.

There is also a long, romantic history of honorable suicide in Japan, from the Samurai avoiding disgrace to the kamikaze pilots of World War II. And suicide is less stigmatized in Japan than in many Western societies.

Mr. ten Hoopen, 38, had entered the Aokigahara Forest wondering why so many Japanese travel there to commit suicide. Although he has a degree in forestry from Velp College in the Netherlands and was with a knowledgeable guide, the vegetation was so dense that it took a few hours to find a way out.

During the week he spent photographing and wandering the forest, Mr. ten Hoopen tried to come to terms with the gravity of his undertaking. “I’m making the same trip — following the same rope, walking in their footsteps, seeing the last trees that person saw,” he said. “I try to visualize this last trip.”

The ropes, put up by people on this last trip, are tied to trees so that others might recover the bodies. Many change their minds, however, and use the rope to navigate back out of the woods.

Pieter ten Hoopen/Agence Vu

Mr. ten Hoopen, a member of Agence Vu, is attracted to topics that are difficult to tell through photographs. Before he arrived in May, he had made a decision not to show skulls or bodies — rather, to explore the subject through subtler images. That turned out to be a fortuitous choice, because he found that the forest had just undergone an annual clearing of bodies by officials and volunteers.

For Mr. ten Hoopen, suicide is a serious and difficult topic. He says he has been depressed at times. Although he was born and raised in the Netherlands, he has lived the last decade in Sweden, another country with a very high suicide rate. This, he said, led him to be interested in the suicide forest story.

“In many ways, the Swedes and the Japanese are similar when it comes to their ways of not really expressing their emotions,” he said. “But Sweden is particularly good for the availability of psychological help. In Japan, seeking this kind of help is less common.”

While mental illness plays a dominant role in suicides, in Japan, there have been upticks during times of particular stress, for instance the financial crisis of 2008 or the tsunami of last year.

It is important to Mr. ten Hoopen that depression and suicide be discussed openly, in all societies. He worries that many — if not most — of the people who enter the Aokigahara Forest to commit suicide “have never spoken to anyone in their lives about their feelings.”

Mr. ten Hoopen was profoundly moved by his guide, the geologist Azusa Hayano, 66, who has spent most of his life in and around the forest and has encountered hundreds of people there, contemplating an end by their own hand. He has persuaded many of them not to kill themselves and rescued scores of others who had already tried and were dying. “He sits down besides them, puts his hand on their shoulders, and just is there as a human being,” Mr. ten Hoopen said.

Pieter ten Hoopen/Agence Vu



Correction, Oct. 25: An earlier version of this post misidentified Mr. ten Hoopen’s nationality. He was born in the Netherlands, not Belgium.

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