Excursion visitors in the quarry Ober-Ohmen. ... Basalt plates in Europe's largest open pit basalt mine, Homberg/Ohm. Sonnberg, Angersbach. Peridotite in Basalt. Christkindches Wiege, Freiensteinau. Diebstein at Lanzenhain. Europe's largest open pit basalt mine, Homberg/Ohm. Trail at the Steiger. Quarry Ober-Ohmen