The audio begins with the soothing hum of a bustling subway station. The low chatter of passengers waiting on the platform fills the background, intermingled with the occasional rustle of a newspaper or the distant echo of footsteps. Suddenly, a robust metallic roar signals the arrival of the subterranean train, its wheels grinding against the track as it pulls up to the station. The mechanical hiss of the train's doors opening follows, allowing a rush of cool air from the tunnel to sweep across the platform. With the familiar beeping sound, the doors close, and the train starts to depart. The unique screech of the wheels against the rails gradually intensifies as the train picks up speed, disappearing into the echoing depths of the tunnel. The platform returns to a relative quiet, with only the faint rumble of the departing train remaining. The audio ends with the station's ambient noise, painting a vivid picture of a typical subway station, moments after the departure of a train.