[2][3] Upon crossing the river, PA 372 enters Martic Township in Lancaster County and passes over Norfolk Southern's Port Road Branch railroad line as it continues into forested areas.

The road turns north as it passes to the west of the Muddy Run Pumped Storage Facility and to the east of the community of Holtwood.

In the center of Quarryville, US 222 turns to the south and PA 372 continues along East State Street through the commercial downtown.

The route passes homes and businesses in the eastern part of Quarryville and intersects the northern terminus of PA 472.

[2][4] At this point, the route enters the Pennsylvania Dutch Country of eastern Lancaster County, which is home to many Amish farms.

The route continues into Bart Township and passes through more rural land before it reaches an intersection with PA 896 in the community of Green Tree.

PA 372 turns southeast onto state-maintained South Bridge Street and runs through woodland with some development on the west bank of the East Branch Octoraro Creek.

The road curves south and passes under the Enola Low Grade Trail before making a sharp turn to the east into the borough of Atglen.

PA 372 follows Valley Avenue through residential areas before turning south onto Main Street in the commercial center of the borough.

A short distance past this intersection, PA 372 crosses back into West Sadsbury Township and heads through farmland with some industrial buildings and homes.

The route turns north onto South Limestone Road and runs along the border between West Sadsbury Township and the borough of Parkesburg to the east before fully entering Parkesburg, passing between industrial areas to the west and residential neighborhoods to the east.

PA 372 enters Valley Township and runs through wooded areas with some fields and residential neighborhoods, heading through the community of Westwood and crossing under an abandoned railroad line.

[2][7] In 1809, the Pennsylvania General Assembly authorized for a road between Parkesburg and McCall's Ferry on the Susquehanna River.

[18] On September 28, 2015, the Norman Wood Bridge that carries PA 372 over the Susquehanna River was closed indefinitely after a crack was discovered in one of the steel girders.