The morning heatwave, having grown rampant on the city skyline, overspills into the streets of Phnom Penh. Our tuk-tuk driver drags a veil of dust through the heavy amber spears of sunlight. He wears a wholesome white cotton shirt and brown fisherman’s trousers. The urban musk of petrol, fruit and rubbish billows the fine fabric into a Michelin Man burlesque. He pilots with patient aggression around meteoric potholes and slaloming squads of mopeds. Rusting Ford trucks flaking green and white paint heave across tight corners, chickens screeching and pallets shifting in the back.

The stain left by the Khmer Rouge draws thousands of genocide tourists to Cambodia every year. Young couples exploring one another; patrician types inspecting former colonies; dirt bike riders seeking unblemished jungle trails; the singlet and hiking boots set aching for non-Western civilisation. In the early morning this temporary diaspora converges at Choeung Ek, the killing field where the Khmer Rouge slaughtered almost 9000 political prisoners.