Columbia subject headings:
Harvard subject headings:
Harz Mountains (Germany)--Description and travel.
Harzklub--History.
Hiking--Germany--Harz Mountains--History.
Nature conservation--Germany--Harz Mountains--History.
Princeton subject headings:
Harz Mountains (Germany)--Description and travel.
Harzklub--History.
Hiking--Germany--Harz Mountains--History.
Nature conservation--Germany--Harz Mountains--History.