The Yangon Circle Train, which winds its way round the suburbs of Myanmar’s former capital, is surely one of the world’s great railway bargains. A ticket for a three-hour journey costs 200 kyat (HK$1.20). The pace is so leisurely, the clackety wheels so hypnotic, the air pouring through the glassless windows (there are shutters for when it rains) so sultry that the carriages have a sign – a boy and a girl mid-clinch with a red line sternly dividing them – that indicates…