Clio Logo

This historical marker was dedicated on April 18, 1985, by the Pennsylvania Historical and Museum Commission. Located next to Pittsburgh's Grandview Overlook, the marker serves as a reminder of Pittsburgh's connection to industries that were connected to the region's bituminous (soft) coal mining. The Pittsburgh coal seam was considered among the most valuable mineral deposits in the United States and fueled the growth of industries in the city and throughout the region. The soft coal from the Pittsburgh coal seam was primarily used to produce coke, the main fuel source for iron blasting furnaces.


  • First Mining of Pittsburgh Coal Historical Marker
  • First Mining of Pittsburgh Coal Historical Marker (Street View)
  • Map of Pittsburgh Coal Seam

Coal mining in Pittsburgh began in the mid-1700s, but bituminous (soft) coal mining became a popular form of mining in 1760 at "Coal Hill" (present-day Mt. Washington). Soft coal has been considered by geologists as the most valuable mineral deposit in the United States because it was the primary fuel source for iron blast furnaces, which elevated the iron and steel industry at the time. Coke was first used in 1817 in Fayette County in Pittsburgh, PA, and gradually, blacksmiths, foundrymen, and iron mill workers began to use coke to aid them with the production of tools, weapons, and other iron and steel-based products. To make coke, workers at iron and steel factories would burn soft coal under controlled conditions to expel gases from the burning coal and use the coal's ash and carbon to form coke. Coke was utilized more than soft coal by itself because coke has more heating power, which heated the iron blasting furnaces easier and faster.

Between the 19th and 20th centuries, the Pittsburgh coal seam was the best suited source to mine soft coal for coke. Located around the southwestern portion of Pennsylvania, the Pittsburgh coal seam was a "hot bed" for high-quality soft coal, which was "purer" than other soft coal mined in surrounding areas and had a higher carbon concentration. These valuable qualities of the soft coal mined at the Pittsburgh coal seam fueled combustion and heating power. During the 1830s, the introduction of beehive coke ovens, dome-shaped furnaces that better helped burning coal under controlled conditions, further expanded on the iron, steel, and coal industries in Pittsburgh. Around the same time of the beehive coke ovens, Pittsburgh was dubbed the "Smoky City" for its heavy coal burning (approximately 400 tons of soft coal was burned daily).

To maintain its title of the nation's steel and iron capital, steel and iron factories in Pittsburgh demanded more coke production, which correlated with an increase in soft coal consumption. Between the late-19th and early-20th, the Pittsburgh seam-mines were introduced, which significantly increased the area's coal production, and in 1916, the steam-mines peaked to 400 million tons of soft coal mined. During this time, due to the increase of seam-mines and its influences with coke production for the iron and steel industries, the late-19th and early-20th centuries has been "Golden Age of King Coal, Queen Coke, and Princess Steel."

Currently, Pennsylvania is one of the biggest coal-producing states in the United States. Over the past 200 years, 10 billion tons of soft coal have been mined and consumed, which is 25% of all coal ever mined in the United States.

First Mining of Pittsburgh Coal Historical Marker, Explore PA History. n.d. Accessed September 2nd 2019. http://explorepahistory.com/hmarker.php?markerId=1-A-2C5.

Powell, Albrecht. Coal Mining History, Disasters, and Tours in Pennsylvania, TripSavy. June 12th 2019. Accessed September 2nd 2019. https://www.tripsavvy.com/coal-mining-in-pennsylvania-2707776.

Image Sources(Click to expand)

https://www.hmdb.org/marker.asp?marker=48882

https://www.hmdb.org/marker.asp?marker=48882

https://www.hmdb.org/marker.asp?marker=48882