Old St Peter's Church is a ruined parish church in Thurso. It dates to at least 1125, and at one time was the principal church for the county, administered by the Bishops of Caithness.
Early in the 16th century, the vicarage of Thorso was held by Sir John Mathesoun chancellor of Caithness, on whose demission or otherwise Queen Mary in 1547 presented Master John Craig to the benefice. Master Walter Innes, who appears in record in 1554, was vicar of Thurso in 1560, and continued to hold the vicarage between 1561 and 1566. About 1567, John Rag was minister, and in 1574, Alexander Urquhart was minister of Olrik and Thurso, and John Davidsoun was reader at Thurso. In 1641, Alexander Monro, minister at Durnoch had from King Charles I, a grant of 800 marks Scots or of eight chalders victual in augmentation of his stipend from the rents of the bishopric in the parish of Thurso and elsewhere.
Old St Peter's, still standing, was disused since 1832 when a replacement church was built for the parish. That church, St Andrew's and St Peter's, is of Gothic style and was built to a design by William Burn.
References:Doune Castle was originally built in the thirteenth century, then probably damaged in the Scottish Wars of Independence, before being rebuilt in its present form in the late 14th century by Robert Stewart, Duke of Albany (c. 1340–1420), the son of King Robert II of Scots, and Regent of Scotland from 1388 until his death. Duke Robert"s stronghold has survived relatively unchanged and complete, and the whole castle was traditionally thought of as the result of a single period of construction at this time. The castle passed to the crown in 1425, when Albany"s son was executed, and was used as a royal hunting lodge and dower house.
In the later 16th century, Doune became the property of the Earls of Moray. The castle saw military action during the Wars of the Three Kingdoms and Glencairn"s rising in the mid-17th century, and during the Jacobite risings of the late 17th century and 18th century.