Purdy much what it says on the tin, what's the furthest you've visited in any compass direction in the World and in the UK (or wherever you live).
For me:
GB
North: Loch Ness, Scotland
East: Dover, England
South/West: Land's End, Cornwall (I've also been to Holyhead in Wales, but apparently that isn't anywhere near as far west as Land's End)
World
North: Lysefjord, Norway
East/South: Sydney, NSW, Australia
West: Liberty State Park, New Jersey, USA