Horseshoe Curve National Historic Landmark

In the early 1800s the Allegheny Mountains stood as a wall between the settled East and the growing West, and getting freight and travelers across them was slow and costly. The Pennsylvania Railroad, chartered to build a rail line clear across the state, faced its hardest stretch in the steep climb over the Alleghenies west of Altoona, a grade too severe for the locomotives of the day. The railroad's chief engineer, John Edgar Thomson, devised an elegant solution. By running the track deep into a side valley, curving it around the head of the ravine, and bringing it back out on the far side, he could lengthen the route enough to soften the grade to something trains could climb. Crews of laborers, many of them Irish immigrants, cut the great curve into the mountainside largely with picks, shovels, and black powder, and it opened to traffic in 1854. The curve became a symbol of American engineering and a strategic artery so important that during the Second World War German saboteurs, landed by submarine, listed it among their targets in a failed plot.

It carried the mightiest railroad in the country through its glory years, and though the Pennsylvania Railroad is long gone, the line it built still carries freight over the mountains today, more than a century and a half after the first train rounded the bend.

The genius of the curve is simple once you see it: the mountain is too steep to climb straight up, so the railroad wraps the track around a valley to make the distance longer and the slope gentler. From the viewing area at the apex you can look across the ravine and see the tracks on the far side, the same line you are standing beside, curved around so that a long train appears to be facing itself as it rounds the bend.

Because this is a heavily used freight main line, the show is close to continuous. Locomotives lean into the curve hauling long strings of cars, sometimes with helper engines pushing from the rear to get up the grade, and the wheels squeal and the ground rumbles as they pass. A short funicular incline, or a stairway beside it, carries visitors from the visitor center up to the apex, where a barrier lets you stand safely just yards from the moving trains.

The Pennsylvania Railroad did not just build a curve here, it built a city. Altoona grew from almost nothing into a major railroad town, home to enormous shops where the company built and repaired its locomotives and cars, employing thousands and drawing immigrants from across Europe. The city's identity, its neighborhoods, and its fortunes rose and fell with the railroad, and its story is told at the nearby Railroaders Memorial Museum.

The mountains the curve climbs were long the homeland of Native peoples, including the Lenape and, in these western ridges, the Shawnee and Haudenosaunee nations, before displacement in the colonial and early national periods. None are federally recognized in Pennsylvania today, and descendant nations continue elsewhere. The great cut in the mountainside is a young mark on a very old landscape.

Spring and summer are the easiest times to visit, with green mountainsides framing the trains and comfortable weather for the climb to the apex. Summer brings the most visitors, though the rail traffic is steady enough that crowds rarely spoil the show.

Autumn is the most beautiful, when the hardwood forest that blankets the curve turns gold and red and the trains wind through a wall of color, a favorite of railroad photographers. Winter is quiet and stark, the trains dark against snow, though the funicular and some facilities may run a reduced schedule, so check ahead in the cold months.

The closest Boutel™ stays, so you can turn this stop into an overnight. Each is an independently owned, editorially selected place to stay.