National Library of Ireland - Catholic Parish Register Images Online

The online images cover most Catholic parishes in Ireland and Northern Ireland up to 1880. The free images, in black and white, are of the microfilms of the original birth and marriage registers held by the National Library of Ireland. There are no image transcripts or indexes on this site The nationwide network of local family history centres holds indexes and transcripts of parish registers for their local areas. See RootsIreland The online help has videos titled Searching for a Parish and How to use the Features. Many of the registers are in Latin and you will find useful advice and links to help
Indexes and images also available from Ancestry.com and Findmypast (Free but need to register for a free account)