But he finds a group of men who are content to direct him back past the bus stop to the town's single hotel, a dismal establishment where this distinguished Swedish writer sits and wonders "OK, perhaps one has to travel. But why exactly here?"
Sven Lindqvist's opening question may prompt some readers to wonder why so many writers feel obliged to travel at all. The pith helmet is in the museum along with the Gatling gun, but publishers are still commissioning marathons of the white-legs-in-the-jungle variety. And nobody needs another book in which travel is served up as the distance you go before fatuous western attitudes become entertaining.
Lindqvist is quite different. He heads into the desert with an ancient word processor so heavy that he needs a native with a wheelbarrow to cart it from one sand-blasted hotel to the next. Presenting himself as a resolutely unheroic figure, he draws on many visits to Africa over decades. As for the 100 floppy disks in his bag, they contain what he takes to be "the core of European thought", excavated over countless days in the libraries of Europe.
His title is quoted from Joseph Conrad's Heart of Darkness, a novella written in the last years of the 19th century, which tells of a voyage upriver into the African continent in search of Kurtz, who has vanished into the savagery of colonialism. Lindqvist first read this book as a young man just after the Second World War, when it appeared to foreshadow the Nazi holocaust.
The connection between 19th-century imp- erialism and 20th-century fascism remains his preoccupation as he travels through the parched emptiness of the desert: noting tiny incidents on the sites of past atrocities; collecting the vivid dreams that still disturb the passing European, and pressing them between his pages, rather as if they were exotic desert flowers.
Conrad's story was written at the height of British imperialism, and Lindqvist establishes it as a thoroughgoing condemnation of colonial violence. He traces Conrad's interest in the imperial expeditions of that time: Stanley's triumphant return in 1889 from a three-year expedition, actually a farcical and disastrous affair, to rescue Emin Pasha from "dervishes" in Sudan. He reviews the necessary technological innovations from Mr Dunlop's invention of the bicycle inner tube, which helped to trigger demand for rubber, to the weapons that made safe slaughter possible - gunboats, rifles and the "dum-dum" bullets used for stopping "savages" but banned from European wars.
Some elements of Conrad's story were lifted straight from outrageous reality. There really was a man, Captain Rom, who decorated the gardens of his house at Stanley Falls with the severed heads of 21 Africans killed during a punitive missions. But others are more philosophical, like the idea of extinction, which Lindqvist traces back to Cuvier, who pointed in the 18th century to the extinction of prehistoric animals. This was elaborated in 1850 by Robert Knox, a race theorist who turned extermination into a fact of nature, arguing that "the dark races" were incapable of becoming civilised, and must instead "go under" to the Saxons.
Charles Darwin loathed the brutality he saw on his travels, including the systematic extermination of Indians in the Argentine. But the great evolutionist still foresaw a time when the "savage races" would be exterminated by their civilised superiors. From then on, "it became accepted to shrug your shoulders at genocide".
Having exposed the ideas that justified European imperialism, and the extinction of native peoples, Lindqvist argues that the Nazi holocaust had its roots in 19th-century European thought. Hitler grew up with the belief that imperialism was "biologically necessary", and entailed the "destruction of the lower races". He was convinced of the need for "living space".
The "Lebensraum" idea was first promoted by the German zoologist and geographer Friedrich Ratzel, who in 1891 insisted that races of "inferior culture" died out because Europeans destroyed them in order to take their land. Ratzel turned territorial expansion into the primary sign of a race's vitality. He also pressed for the creation of a German empire. But it was not until 1904 that Germany got round to exterminating the Herero of South West Africa, and there was little distant Lebensraum left to conquer. So the logic of extermination was brought home to Europe. Ratzel included Jews and gypsies with aboriginal people on the list of "inferior" races, fit only to be displaced. He also saw that the struggle for living space did not always have to take place far from Europe. Hitler was given a copy of Ratzel's work in 1924 when he was in prison writing Mein Kampf, in which he imagined Britain and Germany dividing up the world, with Germany expanding eastward.
Such is Lindqvist's main argument, but it would be quite wrong to suggest that he has written a mere tract about ideas. The book is presented as a sequence of 169 short and beautifully written passages in which his story is mixed with autobiographical reflection. In one section the brutality of colonialism may be traced through contemporary documents, while in the next it may be dreamed or distantly implied in Lindqvist's recollections of being beaten as a child - something that Swedish parents were allowed to do "right up until 1966".
These subjective episodes are not always entirely successful, and editors have tried to persuade Lindqvist to reduce them. Since this book was actually written as the third volume in a trilogy, these passages would be more resonant for readers familiar with the first two (which are not available in English). But Lindqvist has kept this more personal material for good reasons. It allows him to avoid the omniscient, and incipiently imperialist, "I" of conventional travel- writing. It also enables him to suggest that something of imperialism lives on close to the foundation of European self-understanding - fuelling the fascism of Le Pen or the racists who attack immigrant hostels in Germany, Sweden and elsewhere.
A few academics may mutter that this is not a proper history book, and deplore the absence of this year's mandatory theorists from its footnotes. But Lindqvist deserves far better than that. He has written an engaged and engaging book that the general reader can think along with. Were the universities ever to tire of their clotted labyrinths of "theory", they would hail it as exemplary for its lucidity. As for travel, with Lindqvist it has absolutely nothing to do with bouncing impressions off a world you can't be bothered to understand. Instead, it is a way of getting to the root of things, of sticking with intractable realities long after others have moved on, of seeing the picture frame as well as the black man who, at an opportune moment, happens to be carrying it through the dusty square outside the hotel window.