Wow, I had a summer holiday thereabouts, 2007?, at Porthcothan, just south of Harlyn. From there I took a ride up the Camel Trail, which begins at Padstow, and follows the Camel River, and I guess old railway/tram line. Very easy gradient, very fast, groomed double track, busy at the estuary end with mum and dad, but much quieter/more senic later on.
Followed that trail through Wadebridge, Bodmin, Hellandbridge, up to Keybridge where the trail ends, then lanes up onto Bodmin Moor and some crazy trails, but by then I was a bit far in to the ride to go and explore.
I realised I was almost 50km away from "home" and decided to turn back, ended up with 96km for the day. Proper summer epic.