Despite its lovely rural setting, Trenilk House, couldnt me easier to find:
Wherever you are in the UK, head South West by taking the M5 to the end of the motorway. Take the A30 junction (the main route into Cornwall). Travel approximately 48 miles down the A30. Go past the Launceston junction and keep going until you see a BP garage on your left hand side. Get off the A30 at the next junction, about 3/4 mile past the garage. The junction is signposted to Five Lanes, Tregirls & Trenilk. At the bottom of the slip road, there is a mini roundabout, take the 2nd exit, again signposted to Tregirls and Trenilk.
Travel down this quiet rural lane for about 200 yards and you come to a left turn in the road, signposted to Trenilk. This lane is even smaller, travel for about 500 yards, go past the big iron gates of Trenilk Farm on the right and almost immediately on the left hand bend, you'll see the sign for Trenilk House on the edge of our barn. Turn into the drive and the B&B Parking Space is immediately on the left - please park tight to allow room for other cars

Or... just type in PL15 7SA to your Sat Nav which will get you to the Trenilk signpost but not to the house - see above text