How this quirky postwar overspill town became home to Dad’s Army

If you go down to Thetford Forest today, you’re sure of a big autumn surprise. The UK’s largest man-made lowland forest is newly peopled by weird, colourful figures. Three bright red women, naked but for their matching Princess Leia buns, gossip in front of a high green fence; a man with a powder-blue chest and a mottled red body stands alone in a clearing.

To the uneducated eye, they might resemble paralysed, paint-spattered escapees from a nuclear meltdown at a secret paint factory deep in the woods, but the truth is less horrific. The Forestry Commission is marking a century of conservation work at Thetford Forest, and the figures are part of an artistic trail through the trees. 

Until now,…