"board_type"=>"toegandsbord AWD; geen gate hier, maar opening in fence","information"=>"board"
"operator"=>"Amsterdamse Waterleiding Duinen","information"=>"map"
"ref"=>"AWD 18","operator"=>"Amsterdamse waterleiding duinen","information"=>"guidepost"
"ref"=>"AWD 10","operator"=>"Waternet","information"=>"guidepost"
"board_type"=>"historical","description"=>"crash site of Britse Halifax NA 347 on April 13 1945","information"=>"board"