This historic structure report on the Furnace Group at Hopewell Furnace National Historic Site provides a chronology of its historical and physical evolution, describes its various parts, identifies character- defining features, and evaluates the integrity of the structures for the 1820- 40 period of significance. It synthesizes and summarizes the information contained in numerous NPS reports written between 1935 and 2005. These research documents address the historical, archeological, architectural, landscape, and administrative aspects of the many components that make up the Furnace Group.