South Mountain Section
Ridge and Valley Province


South Mountain Section showing geology and shaded relief

The South Mountain Section is an area of ridges partly dissected by deep valleys. The ridges are oriented parallel with the length of South Mountain. Local relief between valley bottoms and ridge tops is generally several hundred feet and can be as much as 1,000 feet. The Section’s highest elevation is 2,080 feet; lowest, 450 feet. South Mountain is formed on metavolcanic and quartzite rocks that have been folded into a broad anticline upon which are superimposed smaller anticlines and synclines. The ridges are formed of resistant rocks while the valleys have been eroded into less resistant rocks.

South Mountain Section occurs in south central Pennsylvania in parts of Franklin, Adams, Cumberland, and York Counties.

Roads where the Section can be viewed include paved roads that run from Hunters Run south of Mount Holly Springs to Mont Alto (mainly Pennsylvania Route 233) and Pennsylvania Route 16 or US Route 30 across the southern part of the Section. There are many unpaved State Forest roads that provide excellent access to the Section. Most of the Section is in Micheaux State Forest.

Outstanding Geologic Scenic Features of the Section include: Bare Rock, Chimney Rocks, Columnar Jointed Volcanics, Devils Racecourse, Eagle Rock, Hammonds Rocks, Lewis Rocks, Mont Alto Gorge, Monument Rock, Stone Head, and The Narrows. Not shown on the Map but in the Section are: near Bare Rock - Browns Spring, Buzzards Roast, Wildcat Rocks, and Virginia Rock; near Eagle Rock - White Rocks and Center Point Knob; near Monument Rock - Buzzard Peak and Chimney Rocks; near Stone Head - Lookout; in Mont Alto Gorge - Chestnut Spring, Pearl Spring, Travelers Spring, and Tarburner Spring; near Pine Grove Furnace State Park - Pole Steeple and Sunset Rocks.

State Parks within the Section are: Mont Alto, Caledonia, and Pine Grove Furnace.

State Forest Natural Areas within the Section are: Meeting of the Pines and Carbaugh Run.

Old Forge is a State Forest Picnic Area and is also within the Section.