The parish is one of the few left in England to still have an exclave. The main body of the parish includes the villages of Warbstow, Warbstow Cross and Trelash and a number of hamlets, whereas the exclave (from which the main part is separated by about 150m) includes the hamlet of Canworthy Water (which is claimed to be in Jacobstow parish).
Warbstow was part of the Launceston Rural District from 1894 until 1974.
One of the many maps available on A Vision of Britain through Time is one from the Ordnance Survey Series of 1900 illustrating the parish boundaries of Cornwall at the turn of the 20th century. This map blows up to show all the parishes and many of the small villages and hamlets.
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