Tertiary volcanism
A key factor for the geological structure was Tertiary volcanism, which occurred in direct response to orogenetic Alpine folding. Volcanism affected the final forming of ore deposits and shaped the Earth's surface.
The regularly shaped hills, which were formed by volcanic chimneys, are prominent landscape features - ideal locations for the construction of Medieval border castles. The youngest Bohemian volcanoes and numerous post-volcanic manifestations are found in the documented region.
Localities:
Andělská Hora, Čedičové varhany u Hlinek, Homolka, Hradišťský kopec, Hůrka u Pavlovic, Kernberg, Komorní hůrka, Krásný vrch, Podhorní vrch, Popovský kříž, Rotavské varhany, Ryžovna, Vinice u Skupče, Vlčí hora, Železná hůrka.
