The Drei-Länder-Stein is a boundary stone at the tripoint of the German federal states of Lower Saxony, Saxony-Anhalt and Thuringia near the Großer Ehrenberg mountain in the Harz.
It bears the inscription: HB (Herzogtum Braunschweig, 'Duchy of Brunswick'), AB (Amt Benneckenstein), which was later changed to KP (Königreich Preußen, 'Kingdom of Prussia'), and GW (Gräflich-Wernigeröder Forstgebiet, 'Comital Wernigerode Forest Estate').
The so-called Iron Curtain including the Convoy Way (Kolonnenweg) ran past this point.
Since 3 October 1990, German Unity Day, the boundary stone has marked the borders of Lower Saxony, Saxony-Anhalt and Thuringia.
The checkpoint box is located in a refuge hut some 50 metres (160 ft) northeast of the boundary stones (ca.