While browsing the book "Guide to North American Steam Locomotives", I saw in the Pennsylvania Railroad steam locomotive roster (after 1900 only) that PRR listed four narrow gauge locomotives:
#9663 2-6-0 Griffith & Wedge built 1909, retired 1928, ex- Ohio River & Western
#9661 4-6-0 Baldwin built 1910, retired 1929, ex- Ohio River & Western
#9684 2-6-0 Cooke built 1916, retired 1934, ex- Waynesburg & Washington
#9687 2-6-0 Cooke built 1920, retired 1934, ex- Waynesburg & Washington
Some misc info from quick research:
https://www.flickr.com/photos/railphotos/207042523/
Ohio River & Western 1883 Map
The Ohio River & Western was Ohio's last narrow gauge railroad. The OR&W operated from Zanesville to Bellaire, Ohio between 1883 and 1931. The railroad served several small communities in the rugged hills of eastern Ohio. In 1912, the narrow-gauge was acquired by the Pennsylvania Raiload, but continued to operate its three-foot trackage until forced out of business by a combination of automobile competition and the Great Depression.
http://en.wikipedia.org/wiki/W..._Washington_Railroad
The Waynesburg and Washington was a 3 ft (914 mm) narrow gauge line between Washington, Pennsylvania and Waynesburg, Pennsylvania. The line was conceived by John Day in 1874 and chartered in 1875, with construction beginning in August 1875.[1] It was converted to 4 ft 8 1⁄2 in (1,435 mm) standard gauge in 1944 and renamed the Waynesburg Secondary soon after. It had steep grades and sharp curves. It had few online industries and was used as an interurban passenger route. It was owned by the Pennsylvania Railroad. It was created on April 4, 1868 and existed until 1976, at which time Conrail declined taking it over. Tracks were removed in 1978.[2]
This last item raises some questions. Was PRR running a narrow-gauge interurban line up to 1944? It might be interesting if someone can dig up more on this ...
Another item: