Twardogóra [tfardɔˈɡura] (formerly Old Polish: Twarda Góra (Hard Mountain), German: Festenberg) is a town in Oleśnica County, Lower Silesian Voivodeship, in south-western Poland. It is the seat of the administrative district (gmina) called Gmina Twardogóra. After the area of the future town was settled by West Slavs in the 7th century, it was part of various Slavic states until it became a part of Poland in 992. In the 14th century it was transferred to the kingdom of Bohemia, under which rule continued until the Prussian invasion in the mid-18th century. The area had a majorly Polish population, which was why the Prussian authorities issued official documents for the region in German and Polish.