A chance tweet yesterday drew my attention to this local fact: the glacier that covered almost all of the British Isles in the last age stopped – just like the Jubilee and Met Lines (and moving at about the same speed as the Jubilee earlier this week) – at Finchley Road. Change here for “milder temperatures”.

Thanks to @Tetramesh for then sending me the link to this BBC documentary where no less a glaciologist than Alan Titchmarsh explains more (ff to 23m57s)