Horseshoe Curve

Altoona, Pennsylvania

History

Transportation to the West from Philadelphia has always been made difficult by the Allegheny Mountains. After the Revolutionary War, there was a big increase in people moving west, thus creating a need for better transportation and communication. The first important turnpike in America was completed in 1794 between Philadelphia and Lancaster. By 1832, over 3,000 miles of road had been built by 220 turnpike companies. The building of canals began in 1797. The first long canal was the Union Canal completed in 1827 between Middletown on the Susquehanna River and Reading on the Schuylkill River.

Starting in 1826 short line railroads were built to move traffic between canals. The Allegheny Portage Railroad and the Columbia & Philadelphia Railroad were part of a state plan for this system. The Philadelphia & Reading Railroad was chartered in 1835 and in 1846 the LeHigh Valley Railroad was chartered. The Pennsylvania Railroad was chartered in 1846 and in 1852 opened a line from Harrisburg to Pittsburgh using the tracks of the state owned Allegheny Portage Railroad. The Pennsylvania Railroad purchased the state own Allegheny Portage Railroad and the Columbia & Philadelphia Railroad giving it a complete rail line from Philadelphia to Pittsburgh.

At the time of the Civil War the basic pattern of railroads in the state was established. Lines were added after the Civil War and by 1890 the state had 8,453 miles of railroad. This increased to 11,693 miles by 1915. In the 1960's this was reduced to a little over 9,000 miles due to decrease in railroad traffic brought on by the automobile and trucks.

However, just after the Civil War the Allegheny Mountains was still the barrier going west. The Allegheny Portage Railroad had reduced the time it took to move people and goods over the mountains but it still required up to three days to cross over and hooked up to another railroad. The Pennsylvania Railroad told their surveyors and engineers to look for a better route over the mountains. What they came up with is now know as the Horseshoe Curve.

Construction was started in 1851 using picks, shovels, black gunpowder to blast the rock and back breaking man power of hundreds of men. The ruble from this work was pushed down the mountain until a flat area was formed where track could be laid. After the first track was laid then this rock was moved to where ever it was needed. Construction was completed and the Curve opened on February 15, 1854 with two tracks being in full operation by the end of the year. In 1898 another track was added and in late 1899 to 1900 a fourth track was added. In 1981 the second inside track was removed due to decline in traffic. The Curve has been in continuous operations since it opened but for a few exceptions. Strikes against the railroads has halted traffic and there has been some weather related closures such as the 1889 and the 1977 Johnstown floods.

The Curve starts at an elevation of 1,594 feet above sea level and runs for 2,375 feet from the beginning to the end of its curvature to an elevation of 1,716 feet above sea level, a difference of 122 feet. The diameter formed by the half circle is 1,300 feet. In engineering terms, the degree of curvature is 9 degrees 15 minutes. The average grade is 91 feet per mile, a 1.8 per cent grade, or a 1.8 foot rise for ever 100 feet run. The uphill rail of each track is two inches higher than the down hill rail to aid in rounding the curve at speed. This puts a tremendous amount of wear on the down hill rail. A normal rail on flat land will last for 20 years. The lower rail on the Curve has to be changed every nine months. It is moved to the upper rail and the lower rail is replaced with new rail.

The average day's traffic is 60 trains in each direction, not counting the helper traffic. For comparison, in 1904, a high point in traffic, there were 168 trains a day.

For more information and pictures about Horseshoe Curve Click on the link below.

Horseshoe Curve!