The forecourt in front of the station was, so I was told, laid with the incorrect paving slabs and then re-done in nice textured [sandstone?].
But take a look at how it's being maintained. All that happens is a man in one of those mobile sweeping trucks makes a squiggly journey over the slabs and leaving a swirly dirty mess behind and the corners and edges are left untouched.
See also the Jubilee Bridges
