Eventually, after a few days, I start keeping a list. Motorcycle helmets, meat, belts, watches, roof tiles, sheet metal, louvred windows. I'm losing track of everything I see for sale by the side of the road. Shoes, bricks, bananas, sunglasses, gravestones.
The space between the front of a building and the gutter hums down almost every street. A squat, red plastic stool is all that is needed to transform those few square metres into cafes, tobacconists and barber shops.
From a bus window, I see a man sitting in a shop carving by hand a statue of Buddha, the shop floor open to the street. For sale nearby are coffee, gas bottles, beer, electric fans, live chickens and mufflers.
Any given busy road in Vietnam would sustain a month of sightseeing, I'm soon convinced. I had barely seven days in which to see a few cities in the country's south.
In Da Nang, the first stop after flying up from our port of arrival in Ho Chi Minh City, high-rise hotels line the road along the beach. All the big global hotel names are here or are soon to be.
Up to the north, perched on a hill, is a gleaming white statue of the Lady Buddha: protector of this fishing-village-turned-travel-metropolis from typhoons. None have made landfall here since the statue was completed, we're told.
On the way to see the statue (gleaming white marble is a local speciality), we stop first to see the basket boats on the beach. Fishermen row these small, round craft out to their fishing boats, anchored just out to sea.
For lunch, we stop at a restaurant that looks straight from the Greek islands. Seafood has been given a vaguely European treatment. The white-washed walls and blue windows frame the activities of a handful of influencers.
Later, we stop for dinner at a German-themed restaurant run by a French expat where we are served meat cooked in a Spanish style. Another night, we dine at a restaurant decked out like a French bistro, complete with red-and-white check tablecloths, but eat quintessentially Vietnamese food. One afternoon, we stop for iced coffees at a cafe where the staff uniform is standard-issue Viet Cong soldier and the decor is jungle military bunker with camouflage netting.
High above Da Nang, skirting around the feet of Lady Buddha, the sound of the city and a million Honda Cub 50s and their ilk, is a world away. A bonsai garden and the temple suggest ancient tradition and the steady march of time. Both opened this side of the millennium.
Back near Da Nang's central market, where a mezzanine teems with clothes of suspect authenticity and the ground floor with a jostling of food and other merchandise, there is a spot where the ferry once pulled in on river crossings. In those days, our guide tells us, there was only one bridge. Now there are six. The city is most proud of the Dragon Bridge, its supports like the creature weaving through the river's water.
Further to the south is a much older city, a remnant of earlier forces of globalisation. Hoi An has been a trading port for centuries, a mix of architectural styles and influences. It also lays claim to great beauty and perhaps the world's best banh mi.
The shop in question - Banh Mi Phuong, since 1989 - has a photograph out the front of when Anthony Bourdain came to visit. The shop looks the same as in the picture, only now there is a line of tourists, holding fistfuls of the few 10,000 dong (a couple of dollars) needed to take up the late Bourdain's recommendation. Is the claim about the best banh mi true? The fresh bread and generous helping of pork makes me think it is in the running for the title.
Most of the yellow-walled terraced houses in Hoi An's ancient city now serve tourist needs: selling clothes, trinkets, leather goods and postcards. Among them are houses preserved as museums. In one - the Tan Ky merchant heritage house - I find a gloomy interior despite an internal courtyard on to which living spaces open without internal walls. In that moment, it seems like the most perfect way to lay out a house: robust and practical without losing the feeling of warmth.
In 1927, as Australia was building The Lodge for the prime minister in Canberra, a new house in a French style was being built for Vietnam's Ngyuen dynasty queen. Standing before the restored house in the remains of the imperial citadel at Hue, this timeline overlap startles me. I had imagined Vietnam's royal family to be a thing of a more distant past.
The citadel, a World Heritage Site, covers an area of about 160 hectares. Walking inside its walls, I imagine the gossip, intrigue and trickery of life in the royal court; mandarins taking walks around the sheltered streets, discussing how they would play politics hand-to-hand. Later that night, a river cruise, this time with a performance of imperial-era music. It has a haunting quality: an elegy for a lost world.
The noise hits you first, I was warned. Then you see it. On the first night in Ho Chi Minh City, we wander down a strip so loud and crowded that being outside the nightclubs seems no different to being in one. On Bui Vien, beer is cheap and spruikers are eager to offer you a table among the tourists, their faces lit up by neon signs and their conversations overpowered by electronic music. Smile, nod, gesture a toast with a bottle of Tiger and do your best to ignore the children trying to sell you chewing gum and cigarettes.
During the day, we are taken to Ho Chi Minh City's central post office, built by the French colonial authorities very much in the style of a train station. Outside, our guide points to a roof and asks if we recognise the building. The glass facade behind it won't put you off, if you know the famous photo: black and white, a helicopter, a ladder full of people trying to evacuate, as a city - and a whole way of life - teeters on the brink. The fall of Saigon, 1975. Not the US embassy, as it is often mistaken for, but an apartment block in the city centre, still standing, despite all that's changed around it.
The War Remnants Museum doesn't gloat about the victory of Vietnamese independence. It praises those who stood against the war and outlines the inhumanity, particularly on the side of those seen as invaders. I hear an American couple muttering something about propaganda, which may be true. I take away a sense of the injustice and cruelty.
The writer was a guest of Vietjet.
Getting there: Vietjet flies to Ho Chi Minh City from Melbourne, Brisbane and Sydney. Return economy flights from Sydney start at $499 - vietjetair.com/en
Staying there: Rosamia Hotel, Da Nang, is five-star accommodation with double rooms from $130 a night - rosamiahotel.com. Deluxe doubles at Hue's five-star Imperial Hotel start at $106 a night - imperial-hotel.com.vn. The five-star New World Saigon Hotel has doubles from $242 a night - saigon.newworldhotels.com/en
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