http://www.marinetraffic.com/de/ais/ho
https://www.worldcruising.com/index.aspx
http://www.navionics.com/dehttp://opencpn.org/ocpn/download
http://www.openseamap.org/index.php?id=openseamap&no_cache=1
http://www.pantaenius.de/en/home/pantaenius-ch.html