Volan III was the inhabited third planet in its star system. This system was located on the Cardassian side of the Demilitarized Zone, and was the site of a Federation colony. This colony was one of the Volan colonies. The world had at least one moon. Lieutenant Commander Calvin Hudson, Starfleet's attache to the Federation colonies in the DMZ, was stationed on Volan III. There, he and various leaders from the other colonies met to discuss relevant matters, including the formation of the Maquis in 2370. That year, Gul Dukat took Commander Benjamin Sisko to Volan III to convince him that there were Federation colonists willing to commit acts of violence against the Cardassians, such as the destruction of the Bok'Nor. (DS9: "The Maquis, Part I")
Raymond Boone, or rather a Cardassian operative surgically altered to resemble him, settled with his family on Volan III to operate a ladarium mining sluice following his return from Cardassian custody after Setlik III. (DS9: "Tribunal")
Background information Edit
According to the script, the pronunciation for Volan was "VOE-lahn". 
According to Star Trek: Star Charts (p. 47) and the Stellar Cartography: The Starfleet Reference Library ("Federation Historical Highlights, 2161-2385"), the Volan system was located in the Alpha Quadrant. The system's primary was a M-class star.