Greenwood Furnace and the surrounding 423 acres encapsulate the history of much of the central part of the state. What today appears as a pastoral park in the forest was an industrial iron plantation from 1834 until 1904, when it ceased operation after the remaining trees were cut. Built c. 2005, a board-and-batten, one-story Visitors' Center (15795 Greenwood Road) has a jerkinhead roof. A display inside tells the story of the charcoal iron furnace that burned nearly an acre of trees daily from the surrounding 65,000 acres of land. Six original buildings and a cemetery remain from the village of Greenwood, which once housed more than 300 employees of the Greenwood Furnace, a subsidiary of the Freedom Iron Works in Burnham, Mifflin County. At its peak in the 1870s, the furnace produced three thousand tons of iron per year in this remote area. Ironically, although the furnace supplied iron for the railroad's rails, the pig iron was always delivered to the rolling mill by mule carts, never by rail. When the company closed, the village became a ghost town, but on-site reunions of the former residents eventually led to its being designated a state park and an American Society for Metals Historic Site. The region's rampant deforestation was reversed after 1906, when the state established a tree nursery here, and in the 1930s, when the Civilian Conservation Corps planted more trees and built a dam, culverts, stone bridges, and wooden pavilions throughout the park.
Greenwood Furnace's older buildings now house administration and maintenance functions and are artifacts of both the iron-producing and tree nursery eras. They include the golden sandstone church with a wheel window in the gable end (1867); a stone ironmaster's house with stables, built in 1834; a bookkeeper's house (c. 1863); the blacksmith and wagon shop (c. 1870); and a meat house (c. 1833). Remnants of several other buildings