The Baltimore & Ohio's Patterson Creek Cutoff, known by the railroad as its Patterson Creek & Potomac Branch, dates to the early 20th century when the railroad began looking at the prospect of making its "West End" more efficient. One idea it would eventually carry out was to bypass then busy and congested Cumberland, Maryland which was a major staging point and junction along the railroad (here the B&O had constructed a large yard and its two primary western main lines, one to St. Louis and the other to Chicago, diverged). The cutoff itself was less than seven miles in length but because it bypassed Cumberland and was only a short, direct distance from its St. Louis main line west of the city the project saved the railroad valuable time and resources in moving through trains.
The Baltimore and Ohio Railroad, “Linking 13 Great States With The Nation.” This was the B&O's slogan for much of its existence and something which it held to for its entire life. The Baltimore and Ohio Railroad, commonly known as the B&O, holds the distinction of being this country’s very first common-carrier railroad (meaning a railroad chartered specifically for public use) being officially incorporated and organized on April 24th, 1827. By being this country’s first common carrier the railroad was instrumental in helping to build and grow not only our economy but also the country itself when the “west” meant the Ohio River.
While never a wealthy railroad throughout its existence (when compared to the likes of its much larger and powerful northern competitors, the Pennsylvania [PRR] and New York Central [NYC] railroads) its legacy will forever be remembered as a survivor and that it put customer service above all else. When the company’s name and existence finally came to an end on April 30th, 1987 it had just celebrated its 160th birthday and witnessed the industry grow from nothing more than few scattered systems to a rail network consisting of tens of thousands of miles linking the country from coast to coast (it also outlived its wealthier northern competitors by over a decade).
The Baltimore & Ohio's Patterson Creek Cutoff was the railroad's attempt to relieve the growing congestion around Cumberland for through trains heading to Keyser and points west. The project began around the turn of the century, officially starting at Patterson Creek, West Virginia at milepost 264.4 and known as the Patterson Creek & Potomac Branch. Protecting the eastern junction was Patterson Creek Tower or FN while the western junction was protected by McKenzie Tower (or CO) at milepost 281.3.
The cutoff had exactly one tunnel, Knobley, and one bridge, which was located just west of the tunnel and crossed the North Branch of the Potomac River. The B&O was able to complete its cutoff by 1904 and the double-tracked route covered just 6.3 miles, according to the official timetable before rejoining the main line at McKenzie, Maryland and milepost 281.3. What's interesting to note is that for trains to use the main line heading through Cumberland required nearly a 17-mile jaunt to cover the distance between Patterson Creek and McKenzie instead of the just over six-mile cutoff (basically the line saved ten route miles and plenty of headache navigating through Cumberland). Below is more information concerning Knobley Tunnel, thanks to the B&O's "Official List" dated January 1, 1948:
Knobley Tunnel: Constructed in 1902 it is located 0.9 miles east of McKenzie Station and carries 3 degrees of curve for a distance of 821.5 feet on its eastern end with the rest of the structure 3,338.4 feet of tangent (straight) track. It is a total of 4159.9-feet long, 23' wide, and 30' high. The tunnel's portals are constructed of stone while the bore is lined with brick.
Patterson Creek Cutoff remained in use as a double-tracked affair until around 1960 when the B&O cut the route to a single line and around this time likewise closed CO Tower. The route remained in use through the 1970s before decreasing freight traffic around Cumberland warranted then Chessie System to abandon the cutoff altogether. Today, the line remains virtually intact save for the track and with Cumberland again a busy and congested junction for CSX Transportation there have been rumors of the Class I looking at the possibility of reopening the cutoff.