The Grave of Major Peter Labilliere, Box Hill, Surrey.
Major Peter Labilliere was a successful 18th century Marine, who in his retirement took to Dorking. He was noted for both his kindliness and his eccentricities, eventually predicting his own death, and requesting that he be buried head-first at his favourite spot on Box Hill. It is suggested by local tradition that his reason for making such a strange request was his belief that when with the world turning topsy-turvy he would be set aright. More academic study suggests his reasons were rather more religious rather than such pure eccentricity. Find out more by reading "Major Peter Labilliere's Grave".
Terrain wise, this is something of a climb from the car park at the bottom of the hill at 51:15.33N 0:19.35W, but other than effort there's no real difficulty in finding the virtual location. For easier access walk from the National Trust pay-and-display car park at 51:14.90N 0:18.75W, which presents much less of a climb. Getting to the real cache, however involves clambering and scrambling. Overall, the virtual is ideal for easy family access, but the real cache should only be attempted by healthy adults or older children.
Virtual phase
Find the location, and take note of all the digits in the order they appear on the marker stone. To claim the virtual only, e-mail the number you construct (preferably to this autoresponder). Do NOT post it here - it will be deleted without quarter. You will receive a confirmation number to include in your log entry. Make it clear in your log that you are claiming only the virtual.
Real phase
To continue on to finding the real cache (significantly more difficult) having discovered the combination number label the digits, starting with the first as "A", the second as "B" and so forth. To derive the co-ordinates of the real cache, take the co-ordinates of the clue, add (A-C-D-E)/1000 to the latitude and (remembering that Westing is negative) subtract (A+B+E+F)/1000 from the longitude (both in minutes), then hunt. EPE at time of recording these co-ordinates was 27 feet. You are looking for looking for a conventional clear polythene 1 litre food storer with a blue lid. But be warned it is WELL hidden. However, even in the middle of summer the cache can be reached without any fear of brambles or stinging nettles. Just be creative about your approach. Consider this aspect of the hunt terrain 3.5, difficulty 3.