From Wikipedia, "The hydrosphere in physical geography describes the combined mass of water found on, under, and over the surface of a planet."

Light fog hangs over Oil Creek, just south of Titusville in Oil Creek State Park.  The park is home to several waterfalls and over fifty miles of hiking trails, in addition to providing a historical perspective on the early petroleum industry.

Oil Creek

From the Ridley Creek State Park website:  "Ridley Creek State Park encompasses over 2,606 acres of Delaware County woodlands and meadows. The gently rolling terrain of the park, bisected by Ridley Creek, is only 16 miles from center city Philadelphia. Within the park boundaries was a small 18th century village, which grew up around the site of a mill. Now known as Sycamore Mills, the area had been previously named Bishop’s Mill and Providence Mill. The miller’s house, the office and library, and several small mill workers’ dwellings are currently used as private residences. The park area has been designated as the Ridley Creek State Park Historic District on the National Register of Historic Places. Park property was purchased in the 1960s with Project 70 funds, and developed with Land and Water Conservation Fund moneys. Park facilities were dedicated to public use in August of 1972."

Waterfall at Sycamore Mills Dam, Ridley Creek State Park

This image, taken on a rainy day, is the stream bed of Rocky Run, with approximately one foot of the channel anchored with plant roots exposed, at Tyler Arboretum in Media, PA.

Rocky Run, Media, PA