Three weeks in China, and in every city on the mainland the skies were dull and grey, filled with pollution. My daily iPhone weather update advised of ‘dangerous’ air quality, time after time. Hong Kong was our last stop, and - what a relief! - gave us sustained blue skies.

David had lived here for several years when he was younger, so we followed his journey, tracking his recollections. Fifty years had passed, meaning his memories were sharp in places, confounded in others - more by the scale and extent of development over the years than by time itself.

The Peak on Hong Kong Island was really something, so high above the incredible cityscape. Our hotel was in Kowloon, behind us, but lost amongst the buildings.