Simply Paul: Found better hidden than I was expecting, but still time to go. The size of this cache makes it a serious Muggle risk and, with tree-cover and 'camoflage' rotting away, I've decided to retire it, with half an eye on new ones for the 2018 Winter Geolympix Mega (fingers crossed) and making space for them. Thanks to everyone who found it and sorry to those who didn't. Physically collected while risking being brained by falling conkers in their spiky husks...
SP