The show primarily features:
* Griff Rhys Jones: As the host and narrator, he is the central figure leading viewers on the journey through Wales.
The series may have featured local people or experts who were interviewed for specific segments, but their appearances are usually brief and their names are not readily available in cast listings.
It's important to differentiate between a documentary series and a scripted drama. "A Great Welsh Adventure with Griff Rhys Jones" is the former, focusing on real-life experiences and locations, rather than a fictional narrative with a cast of actors.