Question: Buncle is a name derived from which medieval fortress?
Sentence (from "Asen's Fortress"): Asen's Fortress (Bulgarian: Асенова крепост , "Asenova krepost"), identified by some researchers as Petrich (Петрич), is a medieval fortress in the Bulgarian Rhodope Mountains, 2 to south of the town of Asenovgrad, on a high rocky ridge on the left bank of the Asenitsa River.
Relevant evidence: No