Revenues at the Book of Kells exhibition at Trinity College Dublin (TCD) last year increased by 21% to €20.2m.
The revenues for the 12 months of September last also include income from the Old Library Shop and guided tours and compare to just €16.7m for the prior year - an increase of €3.5m.
A TCD spokeswoman said revenues last year increased as 900,000 people visited the Book of Kells exhibition compared to 740,000 for the prior year.
"A visit to the Book of Kells remains one of Dublin's most popular and must-see things to do," she said.
TCD students last month barricaded the Book of Kells in protest at college's ties with Israel and a five-day protest camp at TCD by college students ended after the university agreed to the demands of the protesting students.
The spokeswoman was unable to quantify the financial hit to the Book of Kells income caused by the protesting students.
The priceless Book of Kells contains the four Gospels in Latin and the manuscript's celebrity derives largely from the impact of its lavish decoration and its artistry.
The Book of Kells has been on display at the Old Library in TCD from the mid 19th century.
In January of this year, TCD unveiled the new Book of Kells Experience which involves visitors firstly viewing the Book of Kells on display in the Old Library, before entering the Long Room.
Visitors then continue their journey in a new Pavilion in New Square, where stories, collections and sculptures come to life through digital projections in light and sound.
Tickets for the new 90-minute experience include both the Old Library and Pavilion buildings, are €25 with concessions for seniors, students and children.
This is a 28% increase on the €19.50 adult charge that was in place for the 45 minute experience for the Book of Kells and Old Library.
The spokeswoman said that TCD is reworking elements of its long-term project to conserve and redevelop its Old Library, "considering the inflationary pressures that have affected all construction projects nationally".
She said that the proposal to issue a tender for design services will be considered at the University Board meeting later this month.
"Until this stage is finalised we cannot confirm the final budget or completion date," she added.
She said that significant progress to deliver key enabling projects for the Old Library capital project has been made and this includes the conservation-led decant of all the book, manuscript, and archive collections out of the Old Library into secure storage for the duration of building works is complete.
The €20.23m in Book of Kells and related income contributed to TCD enjoying record consolidated income of €513.8m last year as the university had a surplus of €3.8m.
Reporting by Gordon Deegan
