ok, is there any map, website that shows which lines are accessible with JR pass ? So when I travel from one place to another I only look into that map to see whether there exists a connection that the pass can be used. I understand the pass is valid for JR trains (with some exceptions) on JR lines and for some non-JR trains and JR-buses.
If you mean JR buses, none that I know of, and the JR pass does not cover JR highway buses. For other bus companies, there may be a map for some but they are not covered under the pass. The one company you suggest is Nohi, and you can see their map at: https://www.nouhibus.co.jp/english/routebus/ https://www.nouhibus.co.jp/english/
The ferry is not from Miyajima to Shikoku. It's from the main island Honshu to Miyajima (about 10 minutes). If you want to take some other ferry anywhere, you will need to pay separately for it.
Comments
Unfortunately, no.
More info is here:
http://www.japan-guide.com/e/e6040.html#section_get_there
So when I travel from one place to another I only look into that map to see whether there exists a connection that the pass can be used.
I understand the pass is valid for JR trains (with some exceptions) on JR lines and for some non-JR trains and JR-buses.
http://www.japanrailpass.net/img/about_jrp/file/rosen_en.pdf
And you can see the list of trains with surcharges on (Major JR Trains Running Through Non-JR Lines and the Sections Concerned):
http://www.japanrailpass.net/en/about_jrp.html
The one company you suggest is Nohi, and you can see their map at:
https://www.nouhibus.co.jp/english/routebus/
https://www.nouhibus.co.jp/english/
Hope that helps.
The only ferry covered by the pass is the JR ferry to Miyajima. It is much faster by JR trains from Okayama anyway.