The Shawnee, Lenape, and and other Native American tribes walked the length of the Appalachian Mountains to trade with other tribes and also to wage war. The path they wore into the land was called the Warriors Path. But these same tribes also traveled east and west on a trail over the Allegheny Mountains. This trail and its most important pass were both named Kittanning, after a large, prosperous Indian village on the western side of the mountains.
According to a treaty signed by William Penn, the founder of Pennsylvania, the Allegheny area was closed to white settlers. Colonists brutally pushed their way westward anyway. More convinced than ever that the whites would steal their lands, the Delaware and Shawnee who lived in Kittanning raided settlements, killing or capturing the inhabitants. In August of 1756 the Delaware burned Fort Granwell (near present-day Lewistown). As a result the governor of Pennsylvania sent Lt. Colonel John Armstrong to lead an army against Kittanning.
In September of 1756, after a six-hour battle, Armstrong’s troops conquered Kittanning and leveled it. With the destruction of the Indian stronghold, more and more settlers violated the treaty and passed through Kittanning Gap into central and western Pennsylvania. By the time of the American Revolution in 1775, Fort Pitt (today’s city of Pittsburgh) thrived on the western end of the state.
Even with the existence of the Kittaning Gap, however, travel from one end of Pennsylvania to the other was not easy. In the early 1800s a Philadelphian who wanted to visit Pittsburgh had to use the Allegheny Portage Railroad, which meant four grueling days of switching between jarring wooden-wheeled coaches, canal boats, and trains.
Mountain Range: Allegheny Mountains
Elevation: 2,154 feet
Location: Outside the town of Altoona, in central Pennsylvania
The Pennsylvania Railroad Company yearned to lay tracks from one end of the state to the other, to haul passengers and goods and thus make a profit. Despite the wishes of the Pennsylvania Railroad Board of Directors, though, the locomotives simply could not climb the steep Allegheny Mountains. Even with a helper locomotive attached, the railroad engines of that time could not conquer more than a 2% grade (a climb of two feet upward for every one-hundred feet forward). Kittaning Gap had a 4.5% grade.
During this period (mid-19th century), the Pennsylvania Railroad was the largest railroad in the world, with more than 6,000 miles of tracks. Due partly to the leadership of its Chief Engineer and President, J. Edgar Thomson, the PRR was known for high quality construction and for innovation. Thomson had a plan for getting the PRR through the Kittaning Gap and thus to the other side of the Allegheny Mountains. His solution would turn out to be the so innovative that it was considered one of the greatest engineering feats of the 19th century.
Thomson solved the problem of the steep grade by lengthening the distance of the incline — thus decreasing its grade. He hired more than 300 Irish workers to build a unique, horseshoe-shaped curve that ran along the side of a mountain, turned to cross a wide valley, then turned again to run alongside a second mountain. Using only picks and shovels, the workers hacked a narrow ridge into the mountainside. Then they laid three rows of tracks on top of the ridge. As they worked, they threw the rock and dirt into the valley below.
The curve is about half a mile long and about a quarter mile in diameter (from one of the mountains to the other). It was completed in 1854 and supports three railroad tracks.
Horseshoe Curve, as it was called, increased the distance that a locomotive had to pull its cars and in this way decreased the grade. The added distance allowed the grade to remain at 2%. With the help of Horseshoe Curve, Thomson conquered Kittanning Pass. Workers blasted a tunnel through the remaining mountains and — at last! — the railroad reached the other side of the steep Allegheny Mountains. After Horseshoe Curve was completed in 1854, travel time between Philadelphia and Pittsburgh was reduced from four days to half a day.
The challenge of the Alleghenies behind them, the railroads went on to lay tracks west across Ohio, Indiana, and Illinois. They would not encounter another mountain barrier until they reached the mighty Rockies.
Today Horseshoe Curve is not that different from what it was in 1854. For more than 150 years trains have traveled on it as they head eastward or westward. In the upper right-hand corner of the photo below, you can see the steep climb the locomotives would have to make if they headed straight up the mountain. Thanks to J. Edgar Thomson, the locomotives make the more gradual ascent around Horseshoe Curve.
Today people come from all over the world to watch trains bend in half as they chug around the Curve — the locomotives heading in one direction, the caboose in the opposite direction. An average of 51 trains a day go through Horseshoe curve, so train buffs and visitors stand a good chance of seeing at least one train make the curve.
In 1966 Horseshoe Curve was declared a National Historic Landmark.
than Iron Horse
heights were safe
from progress —
then smart Engineer
Barbara Gregorich’s previous blog on mountain passes was Raton Pass.