Long distance walking route - the length of the Gryffe Valley from the source of the river near Loch Thom in Greenock, to the Onyx Sports Centre in Linwood, Renfrewshire.

The website has a good brochure which gives a lot of detail on the history of the route, the villages, and some other planning information. 

https://www.rotary-ribi.org/clubs/page.php?PgID=860660&ClubID=1803