martin remembered the day well : it had begun like so many others on that journey - up early ; bright sunshine ; hot weather ; greeted by their official government guide ; a cup of acrid , black coffee ; and a bumpy ride in the back of a french-built 4wd , along dusty , unmade roads , past a landscape of largely featureless scrub and dunes , only punctuated by the odd low , desolate dwelling and an occasional farmer tending to his herd of goats .