Buttermilk Falls in Beaver County. Homewood Sandstone (link is external) [5], a common building material in 19th century western Pennsylvania, was quarried on the site.
Links
[1] https://www.paesta.psu.edu/sites/default/files/geophoto/buttermilkfalls.jpg
[2] https://www.paesta.psu.edu/earth-science-image/anthrosphere
[3] https://www.paesta.psu.edu/earth-science-image/hydrosphere
[4] https://www.paesta.psu.edu/earth-science-image/lithosphere
[5] https://ngmdb.usgs.gov/Geolex/UnitRefs/HomewoodRefs_2108.html