Wikipedia
Tannerre-en-Puisaye
Tannerre-en-Puisaye is a commune in the Yonne department, in Burgundy, in north-central France.
It is famous for its antique "ferrier" (fr), one of the two largest in France with 31 hectares (over 76 acres) covered, and a listed Heritage Monument since 1982.
A "ferrier" is a mound, hillock or hill made with residues from the extraction and smelting of iron ore.