Gaps of the Allegheny

The gaps of the Allegheny meaning gaps in the Allegheny Ridge (now given the technical name Allegheny Front) in west-central Pennsylvania is series of escarpment eroding water gaps (notches or small valleys) along the saddle between two higher barrier ridgelines in the eastern face atop the Allegheny Ridge or Allegheny Front escarpment. The front extends south through Western Maryland and forms much of the border between Virginia and West Virginia, in part explaining the difference in cultures between those two post-civil war states. While not totally impenetrable to daring and energetic travelers on foot, passing the front outside of the water gaps with even sure footed mules was nearly impossible without navigating terrain where climbing was necessary on slopes even burros would find extremely difficult.

The gaps, formed by small streams provided several usable incline planes or ramps connecting the eastern river valley lowlands to the highlands atop the plateau to the west and north that would otherwise have been unnavigable by animal powered wagons before the mid-1930s. As the map at right indicates, there were but five ways west from the eastern seaboard (colonies) to beyond the Appalachians barrier ridges. The gaps in the Allegheny, all west of present-day Hollidaysburg and Altoona, are by Hurlbert grouped as part of the Kittanning Gorge with the eponymous name borrowed from the Lenape (Delaware nation, once centered in the Delaware Valley, ranging from New York Harbor to the northern Chesapeake occupying Eastern Pennsylvania, New Jersey and Delaware) but made immigrants forced west of the Mountains into empty lands during the 18th century. The streams cutting those various gaps either let out into the Susquehanna River tributaries, the Juniata River or West Branch Susquehanna, so gave the rich Pennsylvania Dutch country access to the interior and the ramp-like valleys climbing to the divide, as did the Main Branch Susquehanna and its tributaries climbing to the ridges overlooking both the Hudson and the Mohawk Valleys.

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