In the town, the river Štiavnica originates and nearly the entire flow in the town is currently located underground (used as a sewer), it gets back to surface only at the bottom of the town. At the time of founding the town, the river flowed across the surface and gave the toen the name. Work Invisible Štiavnica is a three-minute audio track reproduced via public radio in the entire area of town Banská Štiavnica in places where water is led under the surface. Responds to flaccid mention of the river itself and its presence - absence in the city streets. The record of sound of stream was conducted at points of entry of water below the surface and in places where it comes again to the surface in the lower part of the city. Record starts with quiet sound of the inflow, gradually mingle with the sound of inflow and outflow simultaneously and ends with just sound of outflow of the water out of the city.