Not for the faint hearted, no barriers so dont look over the edge if you dont like heights.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/16210667@N02">Craig Sunter</a> from Manchester, UK
CC BY 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/16210667@N02/5800229875/">Hells Mouth, Cornwall 1/6/11</a>