The scenes of Owl Cave were filmed at the Bronson Caves located in Griffith Park in Los Angeles, CA. Incidentally, these caves were also used as the original "Batcave" in TV's Batman series. Being there was rather an odd awakening. Far from being set in the wilds of the Pacfic Northwest, a wider shot of the caves reveals a very familiar, albeit a decidedly southern California setting... the Hollywood sign is just up the next hill!
Interiors were also filmed inside the Bronson Caves. Below, stills from the series followed by a few of my photographs of the cave's interior.