Tioga County Township Formation 
Bradford County Township Formation
Chemung County Township Formation
Tri-County Township Index (80 Towns in Three Counties)
Map Created By Joyce M. Tice
Formation of Our Three Counties
County Formation for the Tri-Counties Area.

In the census of 1790 Tioga County PA was in Northumberland County. Bradford County was in Luzerne County except for a tiny slice on the bottom (New Albany area) that was in Northumberland County. Chemung County NY was part of Montgomery County NY.

In the census of 1800 Tioga County PA was part of Lycoming County. Bradford County was part of Luzerne except for the small part that had been part of Northumberland which was now part of Lycoming. Chemung County was part of Tioga County NY.

In the census of 1810 Tioga County had its present boundaries. Two thirds of Bradford County including the area along its present southern border with Sullivan County PA was part of Luzerne County. The other one third of Bradford County, an area in the northwest corner of the county, including the townships of Athens, Burlington, Smithfield and Ulster was a detached part of Lycoming County. Chemung was still part of Tioga County NY.

In the census of 1820 both Pennsylvania counties had their present boundaries. Chemung County was part of Tioga County NY until the formation of Chemung County in 1836. In the census of 1840 and 1850 parts of what are now Schuyler County were part of Chemung County.

Judy OSLER Newman contributed this information