| Saint Illidius | |
| Death Date: | 385 |
| Feast Day: | July 7; June 5 (locally at Clermont-Ferrand) |
| Venerated In: | Roman Catholic Church |
| Death Place: | Clermont-Ferrand |
| Titles: | Bishop |
| Patronage: | Clermont-Ferrand |
| Major Shrine: | Abbaye Saint Allyre, near Clermont |
Saint Illidius (French: Saint Allyre, Alyre; died 385) was a 4th-century bishop of Clermont, France.[1] To Illidius is attributed the rise of Clermont-Ferrand as a center of religious teaching and culture.[2]
Gregory of Tours mentions Illidius in his work. Illidius is credited with having cured the daughter of the Roman Emperor Magnus Maximus at Trier,[3] and died on the return journey.[4]
His tomb attracted many pilgrims.
The fountain of St. Allyre at Clermont is known for its petrifying water, caused by calcareous deposits.