Question: In which country is the Dreieckiger Pfahl and the former Kingdom of Hanover?
Sentence (from "Dreieckiger Pfahl"): The Dreieckige Pfahl ("Triangular Post") is an historic boundary stone, about 1.35 metres high and made of granite, located southwest of the Brocken, the highest mountain in the Harz Mountains of central Germany.
Relevant evidence: Yes