The tracks of the Alegheny Portage Railroad snaked over the mountains in stair-step fashion. The steep inclined planes were connected by sections with gentle grades called "levels." There were eleven levels, and, like the inclines, each was identified by number.
The railroad trace in front of you was part of Level No. 6, or the Summit Level, the high point of the trip. It ran 1.62 miles between Inclines 5 and 6.
When the railroad opened, horses pulled the railroad cars along the levels. Track was usually laid on stone blocks called "sleepers" rather than on crossties which would have made precarious footing for horses. However, steam locomotives soon replaced horses on nearly all levels.
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Rails on levels were set on stone blocks called sleepers. The 32 miles of levels required more than 150,000 sleepers, some of which remain in place today.
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A locomotive pulling a sectional canal boat approaches a viaduct on a level section of the New Portage Railroad. This re-routed version of the old Allegheny Portage Railroad circumvented the bothersome inclined planes, but operated only two years before it was sold to the more efficient Pennsylvania Railroad Co. in 1857.