 Volcanism affected not only the Sudetes but also parts of the Sudetic foreland being part of a SW-NE oriented Bohemo-Silesian Belt of volcanic rocks.Mantle xenoliths have been recovered from the lavas of a volcano at Ještěd-Kozákov Ridge in the Czech western Sudetes.These pyroxenite xenoliths arrived to surface from approximate depths of 35, 70 and 73 km and indicate a complex history for the mantle beneath the Sudetes.