This is completely amazing, I loved it because it was so far out of the way and peaceful. It is a completely free site with some good signage in key points around the site.
I must agree with other reviews that this place is completely unique for ancient history. My girlfriend is not keen on my love of 'old stones' yet even she was moved by Carn Euny.
There is a stillness and quiet at the site that is amazingly peaceful, it is also one of the few prehistoric sites where you can fully interact with the site, you can touch the same stones that were lived in thousands of years ago. The fogue (cornish storage cellar/temple/bolt hole, no-one knows) is amazing, it is an underground building that is made of stone with bioluminescent moss on the walls.
All in all this is an absolutely amazing site, it is quite hard to follow signs to Carn Euny so obtain some directions from: http://www.english-heritage.org.uk/daysout/properties/carn-euny-ancient-village/directions
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