Some lava tubes from 30 mins, fortunately with subtitles:
http://www.bbc.co.uk/iplayer/episode/b04kg23n/oir-a-chuain-shiairfacing-the-atlantic-episode-3
Mike
http://www.bbc.co.uk/iplayer/episode/b04kg23n/oir-a-chuain-shiairfacing-the-atlantic-episode-3
Mike