Inspired by the successful transport of freight over the Allegheny Front escarpment via the Allegheny Portage Railroad system , during the mid-1830s the business community .
The legislature sought a 26 - mile ( 42 km ) extension .
Inspired by the successful transport of freight over the Allegheny Front escarpment via the Allegheny Portage Railroad system , during the mid-1830s the business community and the legislature sought a 26 - mile ( 42 km ) extension .