Nord-Trøndelag borders Nordland to the north, Sør-Trøndelag to the south, Sweden to the east and the Norwegian Sea to the west. The county seat is Steinkjer, with 20,527 inhabitants (2005). The largest lake is Snåsavatnet and the largest river is Namsen, one of the best salmon rivers in Europe. Other well known salmon rivers are as Verdalselva and Stjørdalselva. Salsvatnet is the second deepest lake in Europe, with a maximum depth of 482 m. Another lake in the area is Byavatnet. Stjørdal is the fastest growing municipality in the county. There are local hospitals in Levanger and Namsos.
A large part of the population lives near the large Trondheimsfjord, which is a central feature of the southern part of this county. In the north are other fjords, mainly the Namsenfjord and Folda fjord. Areas on the eastern and northeastern shore of Trondheimsfjord (mainly in Stjørdal, Frosta, Levanger, Inderøy, Verdal and Steinkjer) are fertile agricultural lowland, with grain fields and vegetables. Together with the grain fields in the Namdalen lowland, this forms the most northern grain cultivation area in Norway today.
Seierstad in Fosnes.However, the spruce dominated forest (some birch) covers a much larger area, and Nord-Trøndelag is the second largest timber producing county in Norway (after Hedmark). The forest and highland in Nord-Trøndelag is one of few places in Norway with four species of deer (moose, roe deer, red deer and reindeer). There are mountains near the border with Sweden, and coastal mountains with bare rock at the northern coast. The spruce forests occurs even at the coast, where some areas belong to the Scandinavian coastal conifer forests, a rare European temperate rainforest (boreal rainforest). There are several national parks in the county, among them Blåfjella-Skjækerfjella National Park (one of the largest in Norway, Børgefjell National Park (partly), Lierne National Park and Skarvan og Roltdalen National Park (partly).