It's a an incredible story - some say unbelievable - about an equally extraordinary historical account just before the turn of the 20th century.

Some time in 1899, a high-ranking white official of the native affairs department in Johannesburg, JS Marwick, organised and led a march of 7, 000 Zulu people out of the City of Gold to their homes in present-day KZN.

The event was sparked by the imminent war between the Afrikaners and the British, and the Zulus and possibly other "natives", had to leave Joburg in a hurry to avoid being stranded in a white men's war.

In the book, Marwick, who too had come from Richmond in then Natal, was ably assisted in leading the march by one complex character named Ndukuzempi - "sticks of war".

Nduku, as he is commonly called, carries the story of the book on his shoulders. From when he escapes unsettling circumstances at King Cetshwayo's court in Zululand in his early teens, to being raised and taught in his later teens by German missionaries, to the mines in Kimberley where he falls in love with a 'white' woman, to a scandal-ridden life in Joburg until the big march.

The author learnt about the Zulu march for the first time just three years ago when listening to a radio interview of academic and writer Elsabe Brink. He wasted no time researching the story, but ended up with a decision to tell it via a fictitious romance between Nduku and his lover, Philippa.

Despite the imagined love story, the book carries in it fascinating aspects of Zulu people's life experiences in Joburg and in KZN - the place Khumalo demarcates into Zululand and Natal, to draw a distinction between the deep rural Zulu heartland north of the Thukela River and the white-administered regions of the province at the time.

The book also reflects on the lifestyles of Zulu workers in Johannesburg, including gangsterism and homosexual practices in men's only hostels, the influences of Christian missions and unpleasant race relations together with attitudes to interracial romance.

The 1899 march is by no means the biggest recorded movement of people in South Africa, as the Great Trek and the Mzilikazi-led march out of present-day Zululand by mainly members of his Khumalo clan and allies, had bigger numbers and covered longer distances.

The Longest March in Khumalo's tale leans more on the test, spiritual and emotional, Nduku and Philippa had to face and overcome before they could know they truly want each other - forever. The 10-day march is difficult and demands the two lovers rely on each other, despite jealousy-driven efforts by Nduku's former best friend, Xhawulengweni, to kill Philippa on the way.

The book is hard to put down; it is fast-paced and rich in history and idiom.

For me, the realisation that the familiar route from Johannesburg to Ladysmith was already in existence in 1899 added a wow factor of a different kind. As a child, I travelled that route by train and in later years of childhood by family car to visit relatives in Standerton and Newcastle, two of the places the book's marchers set camp. I drove the route last weekend.

The only down moment was Khumalo's description of Philippa's community near Kimberley. It's clear from the start that the black and coloured neighbourhood is a dour place and I thought he took too long to belabour that point, when I was in a hurry to return to the march.

The end is also perfectly climactic, with the revelation about the sexual relationship between Xhawulengweni and Ndukuzempi. Philippa, on the other hand, is confronted by the challenge to acknowledge her heritage - white or mixed - as her mother is a Tswana woman.

A must-read for seven thousand reasons.