As has been pointed out, especially in the Carolinas a belt of pine barrens, roughly eighty miles in breadth, ran parallel with the fall line and thus discouraged western advance across this belt, even before the head of navigation was reached. In Virginia, the Blue Ridge made an almost equally effective barrier, walling off the Shenandoah Valley from the westward advance. At the same time this valley was but a continuation of the Great Valley, that ran along the eastern edge of the Alleghanies in southeastern Pennsylvania, and included in its mountain trough the Cumberland and Hagerstown valleys. In short, a broad limestone band of fertile soil was stretched within mountain walls, southerly from Pennsylvania to southwestern Virginia; and here the watergaps opened the way to descend to the Carolina Piedmont. This whole area, a kind of peninsula thrust down from Pennsylvania, was rendered comparatively inaccessible to the westward movement from the lowlands, and was equally accessible to the population which was entering Pennsylvania.[99:1] Thus it happened that from about 1730 to 1760 a generation of settlers poured along this mountain trough into the southern uplands, or Piedmont, creating a new continuous social and economic area, which cut across the artificial colonial boundary lines, disarranged the regular extension of local government from the coast westward, and built up a new Pennsylvania in contrast with the old Quaker colonies, and a new South in contrast with the tidewater South. This New South composed the southern half of the Old West. From its beginning, Pennsylvania was advertised as a home for dissenting sects seeking freedom in the wilderness. But it was not until the exodus of German redemptioners,[100:1] from about 1717, that the Palatinate and neighboring areas sent the great tide of Germans which by the time of the Revolution made them nearly a third of the total population of Pennsylvania. It has been carefully estimated that in 1775 over 200,000 Germans lived in the thirteen colonies, chiefly along the frontier zone of the Old West. Of these, a hundred thousand had their home in Pennsylvania, mainly in the Great Valley, in the region which is still so notably the abode of the "Pennsylvania Dutch."[100:2]