It always starts with a string. A soft vibration in the air that you only feel when you are close enough. The bus shelter stands there like a large, resting instrument, its sound box wide and shiny, its veins spreading across the wood like a score. Finding the opening—that is the first challenge. Because a violin has no clear entrance. Or maybe it is the other way around: maybe all the places where the wood opens up are a possible entrance. But which string do you have to touch to be allowed through? I move slowly along the wood, my fingers gliding over the smooth surface. A subtle resonance under my fingertips. The bridge vibrates as I brush against it; a vibration that travels through the shelter, as if it is trying to say itself: this is where you need to be. But as soon as I move towards the vibrating spot, the sound fades again, the opening disappears like a chord fading in the air.