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USGS National Map viewer after GNIS finding Kittaning Gap Pennsylbania near Altoona PA and showing the PRR Horseshoe Curve. Kittaning Gap by name Pennsylbania near Altoona PA and showing the Pennsylvania Railroad PRR Horseshoe Curve usgs gov NO PFID CPTITLE CTownshipofPortage FrankB other versions PDUSGov Valleys of Pennsylvania