PRR Horseshoe Curve Question

[imphantum]

I've been watching videos, looking at pictures of horseshoe curve in the PRR era, and I've noticed what I THINK is a 5th track behind the actual horseshoe curve.
You can see it at the :30 & 1:15 parts at this video:
http://www.youtube.com/watch?v=jNrPq0Li3P4
And off the the left of the train in this picture:
http://www.billspennsyphotos.com/apps/p ... =130148566
Also, in this picture (below) there is another track on the mountain above the 4 track main:
http://www.billspennsyphotos.com/apps/p ... =130148972
(Credits to the original uploaders)
Now my question is, what were these tracks? Sidings? Branchlines? And when were they removed? I'd love to hear any info on this.

[FourEightFour]

From around the 1860s to just before World War II, the Horseshoe Curve was served by the Kittanning Point station. Two branch railroads connected to the main line at the Horseshoe Curve in the early 20th century; both the Kittanning Run Railroad and the railroad owned by the Glen White Coal and Lumber Company followed their respective creeks to nearby coal mines. The Pennsylvania Railroad delivered empty hopper cars to the Kittanning Point station which the two railroads returned loaded with coal. Across from the station, a spur track on the hillside supplied a coal trestle, where trains could take on fuel and water during the early 1900s.

[imphantum]

Ahh, makes sense now! thanks FourEightFour!