>I read on another site that it was found while clearing the site after a Cork >businessman bought the land to create the park. Looks nice, despite the >obvious renovation of the site.

I bet there's more undiscovered circles in Cork than anywhere else.
I say this because it's sparsely populated, has a high circle ratio, and most of all, lots of the circles are small.

And, it's bloody hard enough to find the ones that HAVE been discovered!