Idstein (German pronunciation: [ˈʔɪtʃtaɪn]) is a town of about 25,000 inhabitants in the Rheingau-Taunus-Kreis in the Regierungsbezirk of Darmstadt in Hesse, Germany. Because of its well preserved historical Altstadt (Old Town) it is part of the Deutsche Fachwerkstraße (German Timber-Frame Road), connecting towns with fine fachwerk buildings and houses. In 2002, the town hosted the 42nd Hessentag state festival.