Gettysburg-Newark Lowland Section
The Gettysburg-Newark Lowland Section consists mainly of rolling low hills and valleys developed on red sedimentary rock. There are also isolated higher hills developed on diabase, baked sedimentary rock (hornfels), and conglomerates. Almost all of the underlying sedimentary rock dips to the north or northwest and many of the smaller drainageways are oriented normal to the direction of dip so that some of the topography has a northeast-southwest linearity. However, the basic drain-age pattern is dendritic. Soils are usually red and are often have a visually striking contrast to the green of vegetation. Relief is generally in the area of 100 to 200 feet, but locally is up to 600 feet on some of the isolated hills. Elevation in the Section ranges from 20 to 1,355 feet. The Section is made up of sedimentary rocks that were deposited in a long, narrow, inland basin that formed when the continents of North America and Africa separated more than 200 million years ago.
The Section occurs in southeastern Pennsylvania and extends from the Pennsylvania-Maryland boundary in Adams County across parts of York, Dauphin, Lancaster, Lebanon, Berks, Chester, and Montgomery Counties to the Delaware River in Bucks County. The Section is crossed by many roads along which the character of the Section can be viewed. Selected routes are: US Route 30 west and east of Gettysburg; US Route 15 from Dillsburg to Maryland; Pennsylvania Route 94 within the Section; Interstate 76 (Pennsylvania Turnpike) from Harrisburg to Morgantown; US Route 422 from Reading to King of Prussia; and Pennsylvania Route 309 from Emmaus to Fort Washington.
Outstanding Geologic Scenic Features within the Section are: Conewago Falls, Cornwall Mine, Dinosaur Rock, Eagle Rock, Falls of French Creek, Governors Stables, Monroe Border Fault, Ringing Rock, Ringing Rocks, Rock Hill, Sentinel Rock, and The Lookout. Others occur at Gifford Pinchot State Park - Balanced Rock; at Gettysburg National Military Park - Devils Den, Little Round Top, and Round Top; at Conewago Falls - Potholes in the Susquehanna River; near Monroe Border Fault - Nockamixon Cliffs.
State Parks in the Section are: Gifford Pinchot, French Creek, Evansburg, Nockamixon, and Tyler. National sites include Gettysburg National Military Park, Gettysburg National Cemetery, and Eisenhower National Historic Site.