A thriving fishing centre, Thurso also had a reputation for its linen-cloth and tanning activities. the Dounreay Nuclear Research Establishment, although mostly decommissioned at the end of the 20th century, employs a significant number of the local population. The Category-A listed ruined Old St Peter's Church (St. Peter's Kirk) is one of the oldest churches in Scotland, dating to at least 1125. The current church, St Andrew's and St Peter's, was built in 1832 to a design by William Burn in the Gothic style.