Lupeni (Romanian pronunciation: [luˈpenʲ]; German: Schylwolfsbach, Hungarian: Lupény) is a mining city in the Jiu Valley in Hunedoara County, Romania. It is one of the oldest and largest cities in the Jiu Valley. It is located on the banks of the West Jiu river within the Jiu Valley, at a height varying between 630 m (in the east) and 760 m.