Here is the link I asked for: http://www.openstreetmap.org/way/183596952

Here is the white hash: https://github.com/prusnak/coinmap/blob/master/img/map/tourist_castle.n.24.png

I imagine it's due to the historic=castle tag.

Please note that the crypto-currency logos are generic, and they should be replaced by more specific ones.

Ciao!