There is nowhere convenient to all 3. Killarney area would probably be the most central but you will end up driving a distance to both Cork city (About 90 minutes minimum, if you don't get caught in traffic in Macroom) and to Dingle(Also at least 90 minutes)
This one is well located
"Dublin might be the best area."
It gets very trying after awhile all right.
Cathy T. I think you will need to have two bases between Cork and Dingle especially if you want to see beautiful west Cork. Glengariff or Kenmare might be good pit stops. Where will you be travelling from and after visiting each place?
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I think two bases is the best idea, but if you were going for one, I would say no further east than Macroom/Millstreet and no further west than Castlemaine. Even so, with those thresholds, you are up to two hours away from one of your destinations.
I stay in Millstreet County Cork when I visit Ireland. I have relatives in the area but I also like it because it is between Cork City and Killarney. I stay at the Wallis Arms which has seven rooms above the pub. It is a quiet and clean place that is competitively priced. There are a handful of restaurants in town, petrol stations and grocery stores. There are two banks so there is a reliable ATM. There is plenty of free parking and it is a very safe little town. The Garda station is right next to the Wallis Arms.
There are decent roads around Millstreet so it is an easy drive to Cork City and Killarney. The other thing that is nice ... there is a train station about a mile from the hotel. It is about an hour train ride to Cork and Cobh is just another 30 minutes. There is also a Catholic church about three blocks from the hotel. It is a great little town but it is a quiet little town.
One of the above comments is right about one thing ... the traffic in Macroom - it sucks!
They are, in fact, actually working on a bypass of Macroom, but I can't say as to when it might be completed.
Not soon enough !!
I stay in Millstreet but attend a Gathering in Inchigeelagh so I have to drive through Macroom. If traffic is bad, and it normally is, it adds 15 or 20 minutes to my trip.
Top tip if you are travelling eastbound through Macroom.and the traffic is bad. Take the left hand turn before the bridge. Then take three right hand turns and it brings you back out on the road to Cork. It works in reverse too, but it's rare that the traffic has backed up towards Cork that you know it when you go through the junction.