What is recorded here

Castledillon Upper holds a wide D-shaped enclosure where St. Illan's hermitage first appeared, later drawing a medieval church, graves and a fine stone effigy into one bounded place. Its low earthen bank still marks the edge of that old religious life, though concrete posts have fallen and gaps now break the line. The name itself changed from Diseart Iollathan to Castledillon, carrying the memory of a Celtic saint into ordinary local speech.

OMURETHI (1909-11, 206-7, 209) records, ' Castledillon … was originally called "Diseart Iollathan" (later corrupted to "Tristledelan"), that is St. Illan's Hermitage, from a Celtic saint of that name … venerated on February 2nd. A large D-shaped area (ext. diam 52m E-W) with straight W side (L 61m) contains a later, medieval church (KD014-016----), a graveyard (KD014-016001-), a possible children's burial ground (KD014-016005-), is the site of a possible early Christain foundation (KD014-016003-), and is the original location of the fine, 13th century 'Castledillon Stone' effigy (KD014-016002-). Defined by a low, partially poached, earthen bank (Wth 6m; int. H 0.1-0.3m; ext. H 0.6-0.8m) topped with concrete posts, most of which have fallen, and a shallow, outer fosse (Wth 1.8-2.5m; D 0.4m). Several gaps give access to the site, the original possibly in the N sector. Compiled by: Gearóid Conroy Date of upload: 10 June 2011

A local fairy fort (ringfort/rath) associated with the hermitage of St. Illan, likely dating to the early medieval period. The site is linked to ecclesiastical use and local folklore surrounding the veneration of a Celtic saint.

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