|Horseshoe Curve-1966. Here is an original photo that I took at the Pennsylvania Railroad's Horseshoe Curve near Altoona, Pennsylvania, during mid-May of 1966. Shown here is PRR engine #9819 and another unit whose number is not legible. Both locomotives were built by EMD. #9819 is an EF-15A built in 1951 and rated at 1,500 horsepower. They are pulling a smokin' eastbound coal train around the Horseshoe Curve and down the Allegheny Mountains to Altoona and points East.