As everybody knows, to a railfan, The Horseshoe Curve, located 6 miles west of Altoona is Mecca It opened February 15, 1854 and revolutionize rail travel. The two sides of the arc are almost parallel, which is an engineering masterpiece, which made conquering the Alleghenies possible. The entire curve WAS visible from the trackside observation area, although now the vegatation does obscure the view. I have gathered my photos from the past.