We are visiting Ireland and aren't renting a car so are looking for the cheapest mode of transportation from Dublin to Blarney Castle.
The cheapest option is usually bus or train from Dublin to Cork then onwards by bus to Blarney. The bus is usually cheaper, but there are often special offers for those who pre-book train tickets.
The Ring of Kerry is 180 miles long, so there are lots of spots to where you could meet up with it. Killarney is the main town along the route and a good place to book a day tour... there are also day tours from Cork.
You can get a snapshot of transport schedules at http://getthere.ie/ -- you'll see more options putting Dublin to Cork rather than Dublin to Blarney. about 5 years ago