Inside information from a man who put together the trailers (which featured music from the Oysterband)

"All the instrumental music was composed especially for the programme, and isn't available to buy (although that may well change if the show turns out to be popular and there's a demand for it). The band was...

Nick Bicat, composer, guitar, keyboards, programming
Danny Thompson, double bass
Peter Knight, violin
Troy Donockley, whistles
Angus Lyon/John Kirkpatrick, squeezeboxes
Kathryn Tickell, Northumbrian pipes
Maartin Allcock, guitar, mandolin, bouzouki, cumbus and other weird
stuff

The song near the end (first episode) was Stranger To Himself by the late and truly great Sandy Denny. The programme was shot in and around Craster in Northumberland. "