It was originally designed by Samuel Diescher,[2] and opened in 1892[3] as part of the Pittsburgh and Castle Shannon Railroad as a means of transporting passenger traffic over Mt.

[5] Before completion of the two Castle Shannon inclines, passenger service was run up the south slope on a route involving a "horseshoe curve" (north of Warrington Avenue and west of Haberman Avenue) and a tunnel that was originally a coal mine, and at the top passengers changed to an older incline to travel down to Carson Street.

Pittsburgh Railways, a trolley system, took over the Castle Shannon passenger service in 1909 and routed their cars through the Mount Washington tunnel that is still in use today.

2 incline for a few years, but it was closed in 1914,[6][7][8][9] with one daily trip being made for franchise purposes until 1919.

[5][10] An undated photograph shows a car with a body like a streetcar on the incline.