Trøndelag (Urban East Norwegian: [ˈtrœ̂ndəˌlɑːɡ]; Southern Sami: Trööndelage) is a county in the central part of Norway. It was created in 1687, then named Trondhjem County (Norwegian: Trondhjems Amt); in 1804 the county was split into Nord-Trøndelag and Sør-Trøndelag by the King of Denmark-Norway, and the counties were reunited in 2018 after a vote of the two counties in 2016.
The largest city in Trøndelag is the city of Trondheim. The administrative centre is Steinkjer, while Trondheim functions as the office of the county mayor. Both cities serve the office of the county governor; however, Steinkjer houses the main functions.
Trøndelag county and the neighbouring Møre og Romsdal county together form what is known as Central Norway. A person from Trøndelag is called a trønder. The dialect spoken in the area, trøndersk, is characterized by dropping out most vowel endings; see apocope.
Trøndelag is one of the most fertile regions of Norway, with large agricultural output. The majority of the production ends up in the Norwegian cooperative system for meat and milk, but farm produce is a steadily growing business.