|South Penn Railroad|
10 (before cancellation)|
Construction never begun|
The Sewickley Tunnel was the last of the original ten tunnels (reckoned east to west) planned on the South Pennsylvania Railroad. It would have been located near the mouth of Sewickley Creek, where it joins the Youghiogheny River near West Newton.
However, while the railroad's right-of-way was still being surveyed, a change in the plans eliminated Sewickley Tunnel. No construction was ever begun at the site, unlike the other nine tunnels which were in various states of completion when the South Penn folded.