The parish lies on the River Tamar (which forms the county boundary between Cornwall and Devon) and the river surrounds Landulph to the north, east and south. Across the river are the Devon parishes of Bere Ferrers and Tamerton Foliot. To the south-east of Landulph is the parish of Botusfleming and to the west the parish of Pillaton. The population in the 2001 census was 485.
Settlements in the parish include the hamlet of Landulph and the bigger village of Cargreen which is on the bank of the River Tamar. The parish church of St Leonard & St Dilpe is in Landulph hamlet. Features of interest in the church include the panelling of the Lower family pew (ca. 1600), some unusual bench ends, a memorial inscription on brass for Theodore Palaeologus (d. 1636), a descendant of the Byzantine Emperors, and a fine tomb of Nicholas Lower, d. 1655. Another brass is a memorial to Elizabeth Lower, 1638.
Wikipedia includes a note about Francis Vyvyan Jago Arundell (1780–1846) who was rector at Landulph from 1805 and was a noted antiquarian.
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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