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Mass Rock Sites beyond the Irish Borders

What is a Mass Rock?


Within the Archaeological Survey Database of the National Monuments Service for Ireland, Mass Rocks are classified as ‘a rock or earthfast boulder used as an altar or a stone built altar used when Mass was being celebrated during Penal times (1690s to 1750s AD), though there are some examples which appear to have been used during the Cromwellian period (1650s AD). Some of these rocks/boulders may bear an inscribed cross’


The Irish name for a Mass Rock is Carraig an Aifrinn. Other names associated with sites where Mass was celebrated in Penal times include Clais an Aifrinn meaning ‘Mass Ravine’, Páirc an tSéipéil or ‘Chapel field’, Faill an Aifrinn or ‘Mass cliff’, Leaca na hAltora indicating a flat stone or rock altar, Cábán an Aifrinn or ‘Mass Cabin’, Cnocan na hAltorach meaning ‘small hill of the altar’ and Gleann an Aifrinn indicating a ‘Mass Glen’.

The Penal Laws were passed between 1695 and 1756. There are many different opinions but no general consensus concerning the severity of persecution resulting from Penal legislation or the myths which have become associated with the Penal era.


So pervasive was the Mass Rock in the image of past persecution that Pope John Paul II spoke of it during his 1979 visit to Ireland. Mass continues to be said at a number of Mass Rock sites today.

Acting as landmarks for the Catholic community, but secreted away from the prying eyes of the authorities, Mass rocks are, by their very nature, difficult to find.

.  .  .  .  .  In Search Of Sacred Space In Ireland

As locations of a distinctively Catholic faith, Mass Rocks are important religious and historical monuments that provide a tangible and experiential link to Irish heritage and tradition.

Gortnahoughtee Mass Rock

One would assume that a researcher may turn to a wealth of already recorded information but the reality of the situation is that Mass rock sites appear to be little researched and what information there is often vague, incomplete or just mind-bogglingly confusing and contradictory.


This website is part of ongoing research which aims to expand the knowledge of Mass Rock sites and place information within the public domain. Research began in the diocese of Cork and Ross, county Cork as part of doctoral studies and is currently being expanded to include the diocese of Cloyne.

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Mass Rock


This website is intended as a two way repository to help identify and record the location of Mass Rock sites across the whole island of Ireland.

By their very nature many Mass Rock sites are often in out of the way places or situated on private land and it is, therefore, not possible to visit all the sites recorded.

However, visitors are welcome to use the information provided, which does include access details to a number of relatively accessible sites. Visitors to the site are encouraged to record details of other Mass Rock sites to help continue to build the repository.

Keem Bay
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