"board_type"=>"nature","information"=>"board"
"addr:country"=>"NL","information"=>"office","source:date"=>"2014-03-24"
"information"=>"map","map_size"=>"site","map_type"=>"street"
"board_type"=>"history","description"=>"De nog enig bewaarde NAM concessiepaal","information"=>"board"