Possible Clues:

• Siren of traditional stories on the French island
• Charmer is lovelier, not very unreliable
• High rock in the Rhine gorge
• Legendary rock that is let roll, for the most part in both cases all the way back
• Singing siren
• Rock singer learning to join blooming band
• Some explore, leisurely, a fabulous Rhine feature
• River temptress
• German siren from tradition that is left over
• Travelling collier, heading off round eastern rock