The No. 9 Coal Mine was first opened in 1855 by the Lehigh Coal and Navigation Company. A large vein of Anthracite coal, known as the Mammoth Vein, was the main focus of mining operations in the Panther Valley. Early mining operations in the area were located in the town of Summit Hill, just above Lansford. As the mines in Summit Hill encountered ever increasing levels of groundwater, other methods needed to be employed to reach the coal. The No. 9 Mine is driven at a much lower elevation than the mines in nearby Summit Hill. As the tunnel was being driven it allowed groundwater to naturally run out from the mine portal without the need of pumps. The tunnel was driven into the mountain far enough to reach the first vein of coal by the end of 1857.

The following year the No. 9 Mine was contracted to produce 90,000 tons of Anthracite coal for the company. The No. 9 Mine operated from 1855 until June 22, 1972, making it the longest continuously operated deep Anthracite coal mine in the world.