Sør-Trøndelag is a county comprising the southern portion of the Trøndelag region in Norway, bordering Nord-Trøndelag, Møre og Romsdal, Oppland and Hedmark. To the west is the Norwegian Sea (Atlantic Ocean), and to the east is Jämtland in Sweden. The county is separated into a northern and southern part by the Trondheimsfjord. Slightly over 200,000 of the county's population (or around 55%) lives in Trondheim and its suburbs. The Norwegian dialect of the region is Trøndersk.

Sør-Trøndelag is a county comprising the southern portion of the Trøndelag region in Norway, bordering Nord-Trøndelag, Møre og Romsdal, Oppland and Hedmark. To the west is the Norwegian Sea (Atlantic Ocean), and to the east is Jämtland in Sweden. The county is separated into a northern and southern part by the Trondheimsfjord. Slightly over 200,000 of the county's population (or around 55%) lives in Trondheim and its suburbs. The Norwegian dialect of the region is Trøndersk.