Turkey Oak, Dulwich Park.
I swear the bike is there - at the bottom - had to get way way back to get all of the beast in and still didn't quite manage it.
Listed as one of the "Great Trees of London".
Really deserves to be in the middle of a large field/prairie but here it is as a sort of border marker in a south london park.
(taken a fair while ago - hence lack of leaves - but I often find deciduous trees out of season have their own beauty and majesty - stresses their long life - they are just watching and waiting for a new summer - one of many - more than we will see quite likely)