The sleek carriages of the KTX, Korea’s express train service, zoom every 20 or so minutes out of Seoul station to Busan at the tip of the peninsula, a journey that takes two-and-a-half hours and is considerably faster, when taking into account time travelling to the airports, than flying.

Such a train may not be unusual in Germany or Japan, but in Korea, the KTX was something of a revolution when it started operating along two lines – to the south-east and south-west of the country – three years ago.