The Kőbánya cellar system or cellar system of Kőbánya (IPA: [ˈkøːbaːɲɒ]; in Hungarian: kőbányai pincerendszer, "cellar system of Kőbánya", or kőbányai alagútrendszer, "tunnel system of Kőbánya"), sometimes known to non-Hungarians simply as the Kőbánya Mine, or the Kobanya Mine, is an extensive network of subterranea, or underground spaces, in the 10th district of Budapest (Kőbánya), in Hungary. It is considered to be the largest cellar complex in the country. The complex as a whole started as an underground limestone quarry in a wine-growing area of present-day Kőbánya in the Middle Ages. Later wineries and beer breweries were established on the premises and they continued to use some of the underground spaces. During the Second World War, the dimensions of the complex enabled it to be use