Castles

Are there any castles in Ireland that are still accessible to the public and safe to walk inside and around?

Mainly looking at ones built around the 12th/13th century? I would say most of them are ruins at this stage but my old home town of Ballincollig still has the main tower and we used to frequently go up there as kids and you could still walk inside it.

I recall visiting Athenry Castle a few years ago - it certainly dates from the period you're interested in.

[broken link removed]

Although it's newer, I enjoyed visiting Parke's Castle as well:

[broken link removed]

And another one....Kilkenny Castle

http://www.kilkennycastle.ie/en/

Navan. Mostly ruins. Guided tours available.
Malahide Castle.
Clontarf Castle ( now a hotel)
Dublin Castle. tours available.

Bunratty Castle and Folk Village - well worth a visit.

Rathfarnham Castle