After our morning at Coombe Mill we headed to the coast to Tintagel Castle legendary birthplace of King Arthur. It has to be one of the most well hidden of English Heritage's portfolio but its worth the hike. However you need not to be afraid of heights and fairly fit to fully appreciate it, I would recommend going on a day when the wind wasn't as strong as we had:
The castle is now just ruins in two parts with the first perched high on the mainland and the second on an island on accessible via a bridge:

