Whithorn is a small burgh in Dumfries and Galloway, Scotland, about ten miles south of Wigtown. The town was the location of the first Christian church in Scotland, the Candida Casa built by Saint Ninian in 397. After this fell into disrepair, a twelfth century priory was built to replace it, but this too has long been in ruins. A museum in the town contains archaeological finds from the site.
Whithorn's link to the sea is the seaport known as the Isle of Whithorn, also linked to St Ninian, and the location of the thirteenth century St Ninian's Church.
A hundred years later the Magnum Monasterium, or monastery of Rosnat, was founded at Whithorn, and became a noted home of learning and, in the 8th century, the seat of the bishopric of Galloway.
It was succeeded in the 12th century by St Ninian's Priory, built for Premonstratensian monks by Fergus "King" of Galloway, of which only the chancel (used as the parish church till 1822) with a richly decorated late Norman doorway, and fragments of the lady chapel, vaults, cellars, buttresses and tombs remain.
In Roman times Whithorn belonged to the Novantae, and William Camden, the antiquary, identified it with the Leukopibia of Ptolemy.