|Horseshoe Curve-1963. Here is an original photo that I took at the Pennsylvania Railroad's Horseshoe Curve near Altoona, Pennsylvania, on 28 September 1963. Shown here (L to R) are PRR engines #5807, #5704, #5857, and #5710. All were built by EMD. #5807, #5704, and #5710 are EP-22's built in 1952 and rated at 2,250 horsepower each. #5857 is an EP-20 built in 1948 and rated at 2,000 horsepower. They are pulling a 50-car westbound mail/express train up the Allegheny Mountains to Gallitzin and points West.