Minefeld and fireships

[John Winner]

Are there any maps or websites out there that show the location of such things as enemy/friendly naval minefields, fireships, marker bouys (such as Elbe I) and other things of this nature? I am trying to plot some U-Boot routes and keep comming across these fire ships and minefields, it would help to plot correct routes if I knew where exactly these items were locatred.

Also names U-Boot routes (example: Weg Blau) and convoy routes would help a lot as well.

John