The Cathach of St. Columba is the oldest extant Irish illuminated manuscript, dated to ca. 600 A.D. The surviving 58 folios contain Psalms 30:10 to 105:13 (Vulgate version).
It is traditionally associated with St. Columba and was identified as the copy made by him of a book loaned to him by St. Finnian, which led to the Battle of Cul Dreimhne in 561 A.D. and to the saint's eventual self-exile from Ireland.
According to the Royal Irish Academy website, however, "It is possible to date the manuscript to the late 6th or early 7th century from the script, but modern historical scholarship has cast doubts on the authorship by St. Columba as well as on the dating."
About the Cathach of St. Columba (Royal Irish Academy)
Royal Irish Academy
Journey to the Cathach of St. Columba (Royal Irish Academy)
The Cathach of St. Columba is located in the Royal Irish Academy Library on Dawson Street in Dublin. In 2009, it was on display as part of an exhibition.
Wikipedia: Catach of St. Columba
Wikipedia: Royal Irish Academy
Ordnance Survey Map (O160337)
The Cathach of St. Columba is on view at selected times. For information, contact the Royal Irish Academy website. General tourism information for Dublin may be found at the Visit Dublin website.
Additional Photos of the Royal Irish Academy
Exterior of Royal Irish Academy, Dublin
Exhibit, Royal Irish Academy Library, Dublin