From http://www.uvm.edu/~jleonard/Ireland/ and released under the GFDL by the photographer, Prof. J. Leonard, Ph.D. according to the following request and response:

Dear Prof. Leonard,

I found your page (http://www.uvm.edu/~jleonard/Ireland/) while doing
research for the free online encyclopedia Wikipedia, and thought
several of your images might be appropriate for inclusion in our
articles concerning Irish ringforts.

I am specifically seeking your permission to use these images:
http://www.uvm.edu/~jleonard/Ireland/ringfort1.jpg &
http://www.uvm.edu/~jleonard/Ireland/ringfort2.jpg

I would like to include your image in these articles:
http://en.wikipedia.org/wiki/Ringfort

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is to create a comprehensive knowledge base that may be freely
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Normally we ask permission for material to be used under the terms of
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You can read this license in full at:
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With your permission, we will credit you for your work in the image's
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Thank you for your time.

Kind regards,

Rich <personal detail deleted>

PS: Any further information on the exact location or name of the
pictured ringfort would be much appreciated. In addition I may want to
downsize the images a little from their current size - please indicate
if you would be happy with my doing so.

RESPONSE FROM COPYRIGHT HOLDER

Hi Rich,

You have my permission to use those images (below) of Ringforts.  The one
in the image is on the Island of Inishmaan (the middle island of the three
Aran Islands).

Thanks for checking with me about the image use.

Jonathan