YOKOHAMA -- Every morning at JR Yokohama Station, people show up armed with brooms and dustpans to clean up litter on nearby streets left by the previous night's carousing throngs.

Until recently, these volunteers lived in a 30-meter section of a closed underground pedestrian passage that used to connect the two sides of the station.

When they arrive at their former "home," they wake up those still sleeping in the tunnel, help them pack their belongings and clean up the walkway.