I love the Minack - seen quite a few plays there. Really worth doing so if you get the chance! Also among the cheapest tickets I've known for a theatre, which is contrary to what I'd imagine! :)

Sennen's lovely. Very popular with surfers (but don't let that put you off! ;) ). It's a big ol' beach... Watch out for that tide tho! Comes in pretty darned quick!

It's difficult to move down there for megalithic sites (and holy wells, if you're that way inclined! :D ) so it's difficult to know whete to start!

G x