‘Trains are wonderful,’ declared Agatha Christie in her autobiography. ‘To travel by train is to see nature and human beings, towns and churches and rivers – in fact, to see life.’ The Caledonian Sleeper invites passengers to jump aboard its 16 coaches in the evening in London or Scotland and wake up at the other end of the UK by morning. Departing Euston every night except Saturdays, the train heads for Glasgow, Edinburgh, Inverness, Aberdeen or Fort William, with stops along the way for people to board. Operated by Serco on behalf of Transport Scotland, it is achieving cult status in these more grounded times when the Swedish concept of tågskryt, translating as ‘train brag’, is the feel-good alternative to flygskam – ‘flight-shame’.