Thanks for your reply! You've chosen a great time of year for a visit to one of Cork's beaches. :)
The walk up to Fountainstown Beach
has some lovely views along the way, and is a great destination for a relaxing day out. It's also helpful that it's not too far from Cork, so you won't have to worry as much about time. You can find the tide forecast along Cork's coastline for up to 7 days by clicking here
What I would absolutely recommend if you're trying to go off the beaten track, is Gougane Barra National Forest Park
. It's not possible to get close by public transport, but About Cork Taxi Tours
organises day tours to this wonderful area. Would this be an option?
Hope this helps! :)