Here goes the street game at the St Martinusbridge, also in Utrecht.

A quote: “So after my almost-arrest I crayoned on – and on – and on – and on. It was more work than I had bargained for to cover the whole bridge. But the weather was nice, the people that passed curious, and no-one in a hurry. So I managed to make the  game quite big, 80 squares in all. Got a lot of questions about the  negative numbers – does no one remember basic math from school? We may be suffering from  dyscalculia as a nation.”

More about this game here