Usually ride down to Cornwall on road bike once a year (to the in laws) but fancy trying it off road as much as possible, ideally in a day, wondered if anyone has tried similar or got ideas of route options.
And yes, i know i could look at a map.

I’ve done Plymouth to Exeter off road in a day which was a top day out.

After a quick look on google you could cut towards Tavistock from Princetown and ride Gawton 😀 but from there i’m a little stuck until you get to Truro for the final leg across Poldice/Carn Brea etc to Redruth.

There must be a way of linking Gunnislake to Truro though.

Could possibly use Sustrans NCN Route 3 (The Cornish Way) to link ‘proper’ off-road areas together maybe?

never done it, sounds like a rad idea though. More power to you.

in one day, off road sounds like a pretty big ask to me even if there is a route.