Charcoal provided the heat to smelt the iron ore. Charcoal was shoveled into the furnace at a rate of 15 bushels per hour. The charcoal house could hold as much as 30,000 bushel of charcoal, enough to keep the furnace “in blast" even during winter months when charcoal was not produced.
Freshly made charcoal was brought by wagon from the hillsides around Hopewell and deposited under the “cooling shed" portion of this building. There it could cool to air temperature to protect against accidental fire before being shoved into the charcoal house for storage until use.
Charcoal kept in this shed is made on site annaully by volunteer colliers.
Source: U.S. Department of the Interior, National Park Service