Ara Mahiva, Easter Island (Chile)
On May 31st 2014 I completed a solo loop around Rapa Nui (or Easter Island): 65.05 kms, 9hrs 5mins. And I think it stands as 'unsupported' - unless you count the little black dog who accompanied me for about 20miles - and the 2 glasses of rainwater I gratefully accepted along the way!!
PHOTO 1: View of the southern coast of Rapa Nui and the site 'Tongariki' - in the middle of the pic is the crater of Rano Raraku (moai carving centre) - and also, in the foreground, my canine companion.