Clark's Ferry Tavern, the oldest building in Duncannon, was originally built by John or Daniel Clark as early as 1788 and later enlarged. It served vital roles as a docking point for the ferry crossing the Susquehanna River, an inn, tavern, and stage stop on the first road westward. Later the building was used as a post office, hotel, dairy and butcher shop before becoming a dwelling and eventually an apartment building. During the Civil War it was known as the Topley Hotel and served as a mustering point for men of Company B of the famed Pennsylvania Bucktails. The structure survived numerous catastrophic floods, damaging modifications and abandonment before being purchased in 2012 in an effort to restore it to its former grandeur.