Sorry for not posting for a while, I've been on a road trip - 1600 miles roundtrip to Pittsburgh and Altoona, Penn. for a research project and a family wedding.
As one whose grandfather and several uncles worked for the Pennsylvania Railroad at Sunnyside yards in Long Island City, NY, or on the NY-Harrisburg-Washington DC corridor, I was quite familiar with PRR heritage.
So, I made it a point while spending three days in Altoona to save a few hours touring the Railroaders Memorial Museum in one of the old shop buildings of the Altoona Works, and then driving about six miles outside of town to spend about two hours at the Horseshoe Curve National Historic Site. The curve was opened in 1854, and has been a highlight to travelers of that section of rail ever since. I had traveled over it many times, including trips to or from the ANA conventions in Houston and St. Louis which I attended via train.
It was a little bittersweet, as the locomotive at the apex of the curve is now a desiel, (until the mid-1980s it was a PRR K-4 steam locomotive), and the trains going around the curve were in Norfolk-Southern colors. However, it was wonderful to appreciate what the curve does - namely, allow the railroad to cross the Allegheny Mountains at a reasonable grade.
There is a 150th Anniversary token available at the Museum gift shop.
The Curve has also been featured on the reverse of at least one Pennsylvania G.A.R. Reunion Medal.