Mahanoy Plane. Critical to the Pa. anthracite industry, this inclined plane railroad transported coal from the Mahanoy Valley up the Broad Mountain to Frackville. Opened in 1862 as part of the Reading Railroad system, improvements in the early 20th century increased its size and capacity, making it an engineering marvel able to meet national demands. After hoisting hundreds of millions of tons of coal, it closed in 1932. Partial ruins remain nearby.