Geologists will tell you that Johannesburg sits on a continental divide, creating a natural watershed, whose rivers and streams flow in opposite directions from the east-west ridge into the two oceans either side of Africa.
One ocean brings a taste of warmth and balmy exoticism to the East, while the other is cold and treacherous.
Johannesburg is a city of immigrants.
The bloody war that brought the Empire’s armies climbing up the escarpment’s aptly named Dragon’s Mountains to march into its dusty but empty streets was preceded by a failed coup by a ragtag group of immigrant prospectors dissatisfied with their treatment at the hand of the Boer government.
It was probably the rivers of gold buried in the hills that form the spine of Johannesburg that was the Queen’s real motive as she called her armies from all corners of the earth to fight a war that left a profound effect on the psyche of her Afrikaaner enemy, whose nationhood was forged at Amajuba, Spioenkop and far off Ceylon.
The All Blacks will launch their own raid on Johannesburg this Saturday and this generation’s prize will be to place their names among the immortals of the sport.
To lose, a watershed of a different kind will be created as the Springboks will start to claw back the golden crown which was once theirs so long ago.
The All Blacks will stay in Sandton in the north, rubbing shoulders with Johannesburg’s nouveau riche who sip their lattés in glitzy shopping malls of shiny steel and glass.
Saturday’s cauldron however is in the immediate south of that golden reef, not far from where Mahatma Gandhi spent spare time in contemplative silence in the hills of Linksfield probably giving life to the ideas that brought that same Empire’s demise.
It is these hills that overlooked the barbed wire blackened landscape of English concentration camps and block houses.
It is these hills that saw a nation’s proudest moments.
On Saturday, their bus will take them through the north’s leafy suburbs past some of the most expensive real estate in all of Africa as it takes the gentle climb to the ridge’s crest where their scenery will change instantly from one side of the road to the next.
The suburbs of Yeoville and Hillbrow have long lost their immigrant residents who called this area home when they left post-War Greece, Italy and Portugal and turned Johannesburg into a little New York of high-rise apartments, all night bakeries, bistros and record stores.
This area is now the home to drug lords and pimps and Africa’s diaspora scratch out a living in old Johannesburg’s crumbling filth.
The bus will take Joe Slovo Drive.
So named after the head of the Communist Party who launched his raids of sabotage against the Apartheid government from his Mozambique hideout.
It is at this stage of the journey that the All Black tour party will slow down to a crawl as they hit traffic on the way down to Doornfontein (translated as Fountain of Thorns), the home of Ellis Park.
80,000 will be making their way along the same route and the crescendo of noise and abuse that will sardonically greet the All Blacks will drive the fact home that they are no longer in pastoral New Zealand.
This part of Johannesburg is Chernobyl’s ugly step-sister. The thieves and gangsters that ply their trades here will on Saturday morph into vendors and car guards as they know better than to take on this army streaming into Ellis Park.
On Saturday they will be on their best behaviour and there is a buck to be made.
By the time the All Blacks get into their change room, their nerves will be shot. By the time they run onto the field, they will be exhausted.
Their Haka will be drowned out by a roar and a hiss. The Springbok howitzers will be fired from afar and their missiles will be falling from earth’s exosphere.
It will be hot and it will be dry and All Black lungs will be on fire in the rarified highveld atmosphere, for it is at times like this that all the conditions are perfect for an irresistible Springbok.
This is not Cape Town with its seductive beauty and cosmopolitan charm.
This is Johannesburg, and this is rugby war.