This is the national tourism body's website and it provides useful information for those who want to cycle in Ireland.
Cycling is a popular activity in Ireland and there is a developing traffic-free cycling route network. Two of the most popular routes are the Great Western Greenway and the Great Southern Trail, both of which are traffic-free routes which make up sections of EuroVelo 1 - Atlantic Coast Route. There are also many sign-posted routes, some of which start in designated Cycle Hub Towns throughout the country. These can be found via the Irish Trails website.
With over 2,000km of unspoilt scenic cycling to explore, Ireland is quickly becoming a mecca for cycling holiday enthusiasts. West Ireland Cycling tours takes you through quaint little Irish towns and villages with B&B and hotel options that are perfectly suited to cycling holidays and very welcoming to tourists. Highlights: Connemara National Park, The Cliffs of Moher, The Burren National Park, The Aran Islands, The Wild Atlantic Way, Traditional Irish Music pubs, quiet country roads