In a narrow valley of the Japanese Alps, a cluster of farmhouses under steep thatched roofs — gassho-zukuri, 'hands joined in prayer' — shaped to carry four metres of snow. Some are three centuries old and still lived in; a couple are open, with the sunken hearth and the loft where silkworms were raised. Lit up on winter evenings above the snow, they are a postcard that turns out to be real.