In 1869, the colliery at Kalmia, PA, opened. Due to its proximity to the Lorberry Creek Railroad at nearby Lorberry, in 1872, the Loberry Extension Railroad extended the line via a switchback on Stony Mountain to reach the mine.
The Philadelphia and Reading Railroad eventually assumed control of the line, naming it the Kalmia Branch.
The branch was abandoned in 1920 under P&R ownership.
See also the Lorberry Creek Railroad, also abandoned, and the Clarks Valley Branch, a further extension of this line, accessed via a double switch back.
