Pennsylvania Highlands Geology

The Pennsylvania Highlands are the foothills of the Appalachian Mountains. The irregular ridges and deep valleys of this unique landscape feature common themes that reflect the region’s geology, which has influenced local history and land use. Much of the Pennsylvania Highlands are comprised of the Reading Prong Geologic Formation. The Reading Prong is found primarily in Berks, Bucks, Montgomery, and Northampton Counties.

Two types of rock are common to the erosion resistant, largely forested ridges of the Pennsylvania Highlands: diabase (basalt), and granitic gneiss and quartzite (see map). The diabase areas create natural limitations for agriculture and land development, due to the size and abundance of boulders. As a result, these areas feature large contiguous woodlands such as Hopewell Big Woods and Unami Hills.

The high iron content in the gneiss and quartzite rock ridges provided the raw material for the region’s industrial legacy of iron and steel. This legacy is reflected in the names of towns, historic sites and parks found throughout all thirteen counties of the Pennsylvania Highlands region: places such as Durham Furnace, Coventry Forge, Hopewell Furnace, Johanna Furnace, Cornwall Furnace, and Pine Forge Furnace. The unique combination of forests, rocky hills, historic sites, industrial towns, and fertile limestone valleys makes for a compelling story to be told through interpretive signage and online tools, enhancing the experience of trail users.

Diabase boulders along the Unami Creek, Montgomery County

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PHTN Proceeds in Green Lane

In their July meeting, the Green Lane Borough Council approved the proposed PHTN route through Green Lane. Read More

Highlight the Highlands: Partners Defend Tohickon Creek, Bucks County

The eastern-most section of the PA Highlands borders the renowned Delaware River from Easton in Northampton County to Washington Crossing in Bucks County,and the area falls within the Lower Delaware Wild & Scenic River System. Read More

AMC Presents Circuit Trails Visual Assessment Project at DVRPC

On Wednesday, June 12th, AMC’s Circuit Trail Visual Assessment project team presented to DVRPC’s Information Resources Exchange Group. Read More

AMC Presents Visual Assessment Project at PALTA Conference

On May 16th, AMC staff presented its study “Protecting Significant Views on The Circuit: A Visual Assessment of Conservation Priorities Along The Circuit Trails” at the Pennsylvania Land Conservation Conference. Read More