The Moltke Watchtower is an observation tower in the Harz Mountains of central Germany, near the village of Lengefeld, in the county of Mansfeld-Südharz in the state of Saxony-Anhalt.
Wikipedia https://en.wikipedia.org/wiki/Moltke_Watchtower
Address 06526, Germany
Coordinates 51°29'34.499" N 11°16'14.827" E