I’m surprised the Chinese girl’s plimsolls aren’t melting as she passes me on the hill. It’s 35°C and rising at the start of the second annual Great Wall Marathon. No amount of sunblock or light-coloured headgear makes it seem like anything less. As this frail form pulls ahead, I...

I’m surprised the Chinese girl’s plimsolls aren’t melting as she passes me on the hill. It’s 35°C and rising at the start of the second annual Great Wall Marathon. No amount of sunblock or light-coloured headgear makes it seem like anything less. As this frail form pulls ahead, I...