At midday, the cluttered streets of Hoi An undergo a transformation: the pea-green French shutters are closed, the crackle of mopeds trails away and, like their former colonial rulers 50 years ago, the locals discreetly withdraw into the relative cool of their ramshackle houses.

The traveller is left with an uncomfortable choice: to return to an airless hotel room with a rickety fan, or to wander the streets on a seemingly futile quest for shade and resuscitation. T-shirts become sodden with sweat, legs grow weary.