In this paper, we report a new occurrence of Myricaria germanica (L.) Desf in a secondary habitat from the north-eastern part of Hungary, from the edge of the Bükk Mountains, in a slag dump in Miskolc. The plant is established on a steep wall formed during the extraction of slag. Due to the erosion of the wall, occasionally a few plants fall off. The age of the dead specimens is between 5 and 13 years, based on their growth rings. The population of about 50 individuals is the largest (but perhaps the only) living population of the species in Hungary. Other rare and protected species (Epilobium dodonaei Vill., Dysphania botrys (L.) Mosyakin & Clemants, Dryopteris carthusiana (Vill.) H.P. Fuchs, Polystichum aculeatum (L.) Roth ex Mert.) have also been found in the slag heap area.