Outside, it’s 20°C and rising, but I’m in the heart of a mountain and shivering in my shorts. I’m on a newly launched experience in the northern Italian region of Trentino, learning how the apple harvest, cheese, and even a data centre is kept chilled in a vast cave complex. “In here we have a steady temperature of 10°C all year.” The voice of Eva, my guide, echoes off the tunnels’ high ceilings. The offbeat, hour-and-a-half in the Heart of the …