Vietnam feels much more prosperous than Cambodia. On the Cambodian side of the border we stutter along a narrow two lane road with dusty verges and fragile skeletal bamboo framed homes right up on the roadside. In Vietnam, we're immediately on a four lane highway, with special scooter only lanes, landscaped central islands and pavements for pedestrians.
The houses are sturdy and painted; the general air of neglect and decay that typifies Cambodia (and lends it some of its laid back charm) is gone. As we enter Saigon (the central distric of HCMC) advertising hoardings, European brands, glass fronted shops and high rise blocks come into view.
There are hardly any bicycles in evidence either. Tuk tuks are replaced by taxis, buses and cars. In Cambodia, outside Pnomh Penh, cars are still relatively rare. They are so valuable that I once saw one parked inside a living room with six broad based wooden armchairs set on the edges of the room around it.
But after the tranquility of Cambodia, where even Pnomh Penh has a faintly rural feel, the traffic in HCMC is startling. Along with the volumne comes a disregard for rules of the road. Some people drive the wrong way because it's easier or more convenient, others use the pavement as a turning cirlce or shortcut.
What's even more startling is that you're expected to brave the chaos and cross the road. There's no point waiting for a gap in the traffic (there never is any) or a green walk signal (they are utterly ignored). You simply need to take your life in your hands, step out and walk.
The secret, believe it or not, is to walk very very very slowly. One tiny footstep in front of the other. This allows car drivers and scooters to estimate your position and take evasive action. They don't slow down much but they do drive round you.
The first two times I try it, I cross in the slipstream of locals, first a young student and then an elderly woman wearing (to my delight) the traditional conical hat. Neither deign to make eye contact with the traffic. They simply keep their eye on their destination and walk, very slowly but deliberately, into the road. At first I watch the cars and the bikes buzz by, but by the end of the day I too am staying zen-like and focused on my target. If nothing else, it's better for my heart rate.
Then I make the mistake of taking a moto home. It's been a long hot day and I don't fancy the walk. But 10 seconds into the longest 5 minute ride of my life, I'm utterly terrified. We whizz along, dodging and weaving. At one point the driver turns to chat to me. 'There are more than 4million scooters in HCMC,' he says proudly.
No kidding, I think, I can see about 3million of them right here, right now, driving straight at us. When I get off my legs are shaking and I'm perspiring with fear. The driver notices my hand shake as I take out the money to pay him.
He touches my arm and smiles. 'You get used,' he says. 'Not long, you get used.'
Not in this lifetime, I think and I swear to myself that I have taken my last motorbike ride between here and Berlin.
And here's a picture for those of you who work in health and safety or maybe municipal electrics. HCMC blows your mind (very possibly literally) with its wiring scheme!