Blood River: A Journey to Africa's Broken Heart
By Tim Butcher
(Grove Press, 363 pages, $25)

In 1874, three years after he greeted David Livingstone on the shores of Lake Tanganyika, the journalist and explorer Henry Morton Stanley set out on another African expedition. This time his goal was to cross the continent from east to west. The journey, financed in part by London's Daily Telegraph, took 999 days. Stanley bullied his way through the Congo River basin, stealing boats and food at gunpoint. Of the 356 members of the expedition, fewer than a third reached the Atlantic Ocean. Of the five white men who set out, Stanley was the only survivor.

Roughly 130 years later, another journalist for the Daily Telegraph set out to follow Stanley's path. Traveling solo, with the help of people he met along the way, Tim Butcher used motorbikes, dugout canoes and (briefly) a helicopter to reach his destination. His trip took 44 days.

Much had changed in the Congo since Stanley's expedition. Although Mr. Butcher's mother had traveled there in 1958, buying colored postcards and watching hippos from a steamboat, by 2004 the Congo was once again a land of deadly diseases and no hospitals, a land where you could travel for miles without seeing an electric light, a land where even cannibalism was not unknown.

The first leg of Mr. Butcher's journey, from Lake Tanganyika to the Congo River, was the most perilous. Here in the eastern Congo was the epicenter of the First and Second Congo Wars, conflicts triggered when Hutu refugees poured into the country following the genocide in Rwanda. Though largely ignored by the outside world, the Second Congo War (1998 to 2003) was the deadliest conflict since World War II. The war killed four million people, according to the figures Mr. Butcher cites, but the effects of continuing hostilities have claimed a million more.

As the author jounces over rugged forest paths on a motorbike, he comes upon a settlement where human bones lie scattered, "white among the green undergrowth." Yet more unsettling than what he sees is the knowledge of all that is hidden or unknown. As roads crumble and people hide in the forest, each village is cut off from the rest. When Mr. Butcher asks about a local massacre where thousands died, no one seems to know about it. "There have been many attacks and many massacres," one man says. "When it happens we flee into the bush, but nobody ever knows the details."

The recent book "The World Without Us," by Alan Weisman, asks us to imagine what the Earth would be like without people -- if no one were around to tend the power plants and pump out the subways and repair the roads. The Congo provides a glimpse of that world. Walking one day along the forest floor, Mr. Butcher feels his boot "clunk into something unnaturally hard and angular." He digs down and finds a section of abandoned railroad track.

"It was a moment of horrible revelation," he writes. "I had discovered evidence of a modern world that had tried -- but failed -- to establish itself in the Congo. . . . I was travelling through a country with more past than future, a place where the hands of the clock spin not forwards, but backwards."

"Blood River" is a satisfying real-life adventure. Mr. Butcher tells what it's like to relieve oneself over the side of a wobbly wooden dugout or to live on cassava root that tastes like a "nasty blend" of wallpaper paste and cheese. But he is also haunted by the question of how the Congo got the way it is and what can be done to change it.

The Congo is not decaying due to lack of resources. Despite years of exploitation, the country still has enormous mineral wealth. And the Congo's plight is not the fault of the Congolese people. Though he meets some thugs and greedy officials, Mr. Butcher is helped by guides and priests and villagers who show integrity and resourcefulness in the struggle for survival. He is never robbed, though anyone could guess that a white man traveling alone through the Congo must be carrying large sums of money.

Mr. Butcher never offers a prescription for the country, but more than once he is told that it needs law and order. Without it, hard work goes unrewarded, criminals are unpunished, hotels and factories crumble away. The United Nations tries to do its part -- its biggest peacekeeping force is in the Congo -- but without strong support from national governments, its efforts fall short.

Early in "Blood River," Mr. Butcher writes: "For me the Congo stands as a totem for the failed continent of Africa." This is not quite fair. Many African countries are doing better than the Congo, which has its own unique history and challenges. Its size and its natural resources, the very things that make it look promising, have also made it hard to govern and easy to exploit. Yet Mr. Butcher's empathy for the people of the Congo is obvious, and when he describes the country as a "triumph of disappointment over potential," it is hard not to share that disappointment and to hope that, at some point, the potential will become real.

Mr. Wisner is the author of "A Basket of Leaves: 99 Books That Capture the Spirit of Africa" (2008).